Reliability of reception

What about large parts of Kabbalah, especially the later Kabbalah? Doesn't the Rabbi see anything strange?
A book that came out of nowhere, not mentioned anywhere, that is suddenly attributed to the Rashi, even the house and wife of the publisher of the book claimed that he fabricated it out of spite for the sake of money, when all scholars unanimously believe that it is late, and even the sages believed that large parts of it were copied, as Ya'avetz showed in Mitfak Sharif.

Beliefs that were clearly influenced by Greek philosophies, mainly Platonic and Neo-Platonic, and also a certain affinity with the beliefs of Gnostic sects (even if it is not clear how much they were influenced by those sects, if at all)
Concepts that were clearly taken from Muslim alchemists, beliefs such as reincarnation that have no trace in the Bible and that even geniuses and rishonim came out against (and absurdly, the first to believe in reincarnation were the Second Temple sects, with the first documented source after their disappearance being Anan Ben David, the founder of the Karaite sect or one of them).
Also, contradictions between the Rashi in the Mishnah and the ”Rashi” of the Zohar.

Does Kabbalah really have an ancient tradition? Are there not problematic beliefs here? After all, there are many fulfilling descriptions there. Many see them not as they are, but there were quite a few Kabbalists who believed in it as they are. There are also laws that contradict the Talmud and the Rishonim and were ruled contrary to the accepted rules of halakhic law, from books that "fell" out of nowhere. When even a prophet is unable to renew new laws for generations.
Is it serious to rely on such problematic traditions and chains of transmission?

You make quite a few factual assumptions regarding the Zohar, and although I have not thoroughly examined them, I think they are debatable. In any case, those who give it validity believe that the tradition about it is reliable. The contents can always be arranged.
Correlations to the perceptions of other groups do not mean much. Both because it is legitimate to be influenced and draw from others (this was certainly also the case with Chazal and in all generations), and also because sometimes the direction of influence could be the opposite (from the Torah to others).
I think discussing the opinions of others is unnecessary and unhelpful. If you are interested in someone's opinion, ask them.
I can only tell you what my opinion is, if there is a concrete question here.

Regarding the Zohar, there is no scholar who believes that it is from the time of Rashbi. There are some disputes about the identity of its author or authors, but it is agreed by all that it is later than Rashbi.
It is also possible to see contradictions between Rashbi's opinion in the Mishnah and the opinion presented in the Zohar, a basic lack of understanding of the geography of the Land of Israel, language breakdowns, and more.
There is also documentation that Di Leon's wife and daughter claimed to have stolen it from him.

Influences can be in the opposite direction, but in my opinion it is much more likely that the Kabbalists were influenced by Greek philosophy. Especially since the first documentation of these concepts was among the Hellenists and believers in the Greco-Roman mystery religions, and the Greek philosophers on whom they were based probably lived without significant contact with the Jews, with the connection of the Ancient East to their views coming after the conquests of Alexander the Great.
It is also possible to claim that Little Red Riding Hood lived 200,000 years ago, invented writing, and developed the entire infinitesimal calculus, discovered the theory of relativity and recorded everything in a book that was kept secret and in the event that Newton, Leibniz, Cauchy, Darbo, Riemann, etc. and Einstein read the book and attributed everything to themselves, or were part of a secret cult that forbade the book from being published. But this is much less likely.

In any case, it is not critical.
My questions are
Can we trust the antiquity of the Zohar? In my opinion, if such evidence were presented in any other field or subject, or in a court of law, it would not be accepted and its origin is questionable and even if there is some doubt, it is null when there is an organized tradition that claims the opposite. Especially when the evidence is very questionable.
The question also arises as to how a book that no one has heard of and has not been mentioned anywhere suddenly appeared?

Additionally, what about the contradictions between Halacha and Kabbalah? If both traditions are correct, or have the same authority, how can there be a contradiction? Or rather, how do you decide between them? It is accepted that one follows the revelation, but there are quite a few who know this and rule according to Kabbalah, and I have not seen anyone object or protest their decisions.

What is the attitude towards other interpretations, such as the rationalists like Maimonides? In the Rabbi's opinion, is their opinion invalid in the face of Kabbalah? How should one treat them?

You are mixing up two questions. The antiquity of the book is not related to the antiquity of its sources. Even if there is a later editing, there are certainly ancient passages in it.
By the way, how many scholars do you think think that the five Pentateuch are from Mount Sinai? About the same number as those who believe in the antiquity of the Zohar.
There are contradictions and disagreements even within the revelation. So what?
No one is null and void before anyone else, since no one has authority (so there is nothing to nullify). Decide what interpretation you think and act accordingly.

The late editing may explain language glitches, but how does it explain things like a commentary on punctuation when punctuation was invented in the ninth century and even then it was different from today's punctuation? Or the incorrect factual description of the Ai?

And let's assume that these are late additions and the rest of the text is ancient. How can one explain the Amoraim who are mentioned as sitting with the Rashbi or his students when hundreds of years separated them? And when all the learning is with them.
That is not possible. Of course, one can make arguments such as there was a quantum leap and the book came from another dimension where those sages lived together or went back in time or that the Rashbi moved in a cave at close to the speed of light and when he came out he arrived at the time of the Amoraim. Or that the dating in the Talmud is wrong and the Zohar is correct.
But again, this is unlikely (just as in a Beit Din or secular court such arguments would probably not be accepted).

Or the mention of non-existent Tanais who happen to mention Greek philosophers by name and happen to say similar things as those philosophers (usually with a slight distortion or the text confronting their method).
How exactly do the language distortions explain this or prove that the text is ancient to the Rashbi's time?
Of course, without getting into apologetics.

Most of those interpretations do not claim information from Sinai or the Tanais. If we assume that the Zohar is from Sinai or the Tanais, then other interpretations cannot be accepted.
Of course, a person who does not accept Kabbalah will not be moved by this, but a person who accepts Kabbalah will see it as heresy. If the rabbi accepts its antiquity, how can he accept new interpretations that contradict the Zohar?

Also, what does the rabbi think about the head ointment? There are also ancient rulings there, but it is accepted that the book is a forgery. It can also be justified with the same arguments.

I wrote that I do not consider this to be an authoritative source, but rather an interpretation. So what do I care if it is early or late? You keep returning to this irrelevant discussion.
And what about that and the perfume? There it doesn't matter at all that it is fake. Examine his arguments and accept what you think and reject the rest. What is the problem at all? That is why I also do not see any problem with such a fake. I have written here in the past that in my opinion it is permissible halakhically (according to the Maga and the Gemara on hanging from a tall tree).