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 Rashbi, even the family and wife of the book's publisher claimed that he fabricated it out of spite for the sake of money, while all scholars unanimously believe that it is late, and even sages believed that large parts of it were copied, as Ya'avetz showed in Mitfak Booken.

Beliefs that were clearly influenced by Greek philosophies, mainly Platonic and Neo-Platonic, and also a certain affinity with the beliefs of Gnostic sects (although it is not clear how much, if any, they were influenced by those sects).
Concepts that were clearly taken from Muslim alchemists, beliefs such as reincarnation that have no trace in Hazal and even geniuses and rishonim came out against them (and absurdly, the first believers 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).
There are 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 as not literal, but there were quite a few Kabbalists who believed in it literally. There are also laws there that contradict the Talmud and the Rishonim and were ruled against the rules of Kabbalah 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 Zohar, and although I haven't checked thoroughly, I think they are debatable. In any case, those who give him validity believe that the tradition about him 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 the Sages and throughout the 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 it is from the time of Rashbi. There is some disagreement regarding the identity of its author or authors, but everyone agrees that it is later than Rashbi.
One can also see contradictions between the 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.
And there is also documentation that De Leon's wife and daughter claimed that she cheated on him out of love.

Influences can be in the opposite direction, but I think it is much more likely that the Kabbalists were influenced by Greek philosophy. Especially since the first records of these concepts were 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 that Newton, Leibniz, Cauchy, Darboe, Riemann, etc., as well as Einstein, read the book and attributed everything to themselves, or that they were part of a secret cult that forbade the book from being published. But this is much less likely.

In any case, it's not critical.
My questions are:
Can the antiquity of the Zohar be trusted? 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 and void when there is an organized tradition that claims the opposite. Especially when the evidence is very questionable.
The question also arises: how did a book that no one had heard of and was not mentioned anywhere suddenly emerge?

Additionally, what about the contradictions between Halacha and Kabbalah? If both traditions are correct, or have the same authority, how is there a contradiction possible? Or rather, how do you decide between them? It is accepted that one follows the revealed law, 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 rationalists like Rambam? In the Rabbi's opinion, are their opinions invalid in the face of Kabbalah? How should they be treated?

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 earlier 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 antecedents of the Zohar.
There are contradictions and divisions even within the revelation. So what?
No one is null and void in front of anyone else, since no one has the authority (so there is nothing to nullify). Decide what you think the interpretation is 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 was different from today's punctuation? Or the incorrect factual description of A.Y.?

And let's assume that these are later additions and the rest of the text is ancient. How can we explain the Amoraim who are mentioned as having sat with the Rashbi or his students when hundreds of years separated them? And when all the learning is with them.
This is impossible. Of course, arguments can be made such as that 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 secular court or tribunal, such arguments would probably not be accepted).

Or the mention of non-existent terms that 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 disruptions explain this or prove that the text predates the Rashbi's time?
Of course, without getting into apologetics.

Most of these interpretations do not claim information from Sinai or the conditions. If we assume that the Zohar is from Sinai or the conditions, then no other interpretations can be accepted.
Of course, a person who does not accept Kabbalah will not be moved by this, but a person who does accept Kabbalah will see it as heresy. If the rabbi accepts his predecessors, how can he accept new interpretations that contradict the Zohar?

Also, what is the Rabbi's opinion on head perfume? There are also ancient rulings there, but it is accepted that the book is a forgery. It too can be justified with the same arguments.

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