1. Is there a prophecy in the Torah from the Holy One, blessed be He, that falls into the category of “what is likely to happen” and that ultimately did not occur?
2. I asked about the verse above because of how comprehensive the knowledge in it is. On the face of it, this does not look like a forecast or an estimate, and it is not phrased that way either, but rather like a very clear viewing of the future, including the exact years and how it will end.
On the one hand, I very much connect with your theory and it sounds logical, but on the other hand the verses imply that everything is foreseen down to the finest details.
For example, I might be able to predict that a person with violent behavior from a young age will end up in prison in the future, but I cannot really know for how many years and for which specific crimes, and what the fate of the judge and prison guard will be, etc. That already goes beyond the likely scenario.
There is a difference between:
So-and-so is a violent child, and presumably in the future he will be behind bars
and:
So-and-so is a violent child; in the future he will assault a person named so-and-so, and he will serve 10 years in prison in Be’er Sheva, and afterward he will reform.
If I say the latter sentence emphatically, then presumably I have future knowledge that nobody else has, and this is not just general speculation at all.

That is why I gave two options.
By the way, the details of this prophecy were not really fulfilled exactly. It was not 400 years but 210. Notice that this is the only concrete detail here. Beyond that, the Holy One, blessed be He, has infinite knowledge and understanding, so it makes sense that He would know details too and not only something general. Free choice determines whether it will happen or not. But as I said, none of this really changes the point.

And another aside: there are several indications that here people’s free choice really was taken away:
The descent to Egypt: “You intended me harm, but God intended it for good.” His plan, not yours.
The enslavement: “And the Lord hardened Pharaoh’s heart.”
The great possessions: “And the Lord gave the people favor in the eyes of the Egyptians” (and not for nothing do the Sages expound: so that that righteous one should not say, “He fulfilled ‘and they will enslave them and oppress them,’ but He did not fulfill ‘afterward they shall go out with great possessions’”).
And of course, “But I will also judge the nation that they serve”: that is entirely in the hands of the Holy One, blessed be He.
So God did not know in advance what would be chosen; rather, He took away the choice and brought it about Himself.

Moed Katan 28:

“Rava said to Rabbah bar Mari: It is written concerning Zedekiah, ‘You shall die in peace,’ and it is written, ‘And the eyes of Zedekiah he put out’ (Jeremiah 39:7). He said to him: This is what Rabbi Yohanan said: Nebuchadnezzar died in his days. And Rava said to Rabbah bar Mari: It is written concerning Josiah, ‘Therefore, behold, I will gather you to your fathers, and you shall be gathered to your grave in peace’ (II Kings 22:20), and it is written, ‘And the archers shot King Josiah’ (II Chronicles 35:23). And Rav Yehuda said that Rav said: They made him like a sieve. He said to him: This is what Rabbi Yohanan said: The Temple was not destroyed in his days.”

The Talmud raises the problem of a prophetic promise not being fulfilled (and note Maimonides, according to whom a good promise given by a prophet must be fulfilled) and resolves it through a very minimal fulfillment of the promise.