WIY – you are right that it may not necessarily completely remove bechira, but because many of our choices are based on the knowledge we have, and we are certainly affected by what others tell us, you might say that psychologically, if Eliyahu were tell me what I would do in the future, and I believe him, that may have a very strong influence on my decision to perform said action. Since I know that I will choose to do an action, my actions certainly FEEL forced to that action. Technically bechira may still be mine, but if I know the result then any perceived bechira is gone. As you said, “you will still make the choices you make for the the reasons you make them” – well in this case, the reason I am making that decision seems to simply be that I have been informed that I will make that decision.
Das – infallibility does not necessarily remove bechira; If you are reading a book for the second time, and you are up to the ending, you KNOW what the ending will be, but does that knowledge determine what the ending will be? No – it’s determined by whatever the author decided to write when he wrote the book. This is even though there is no chance you will be wrong, because you have already seen the ending. So imagine that Hashem has already read the book of history, from its beginning to its end. Although Hashem’s knowledge of events that will occur is perfect and flawless, that does not contradict the possibility that we humans, as the collective writers of the story through our actions and decisions, are using bechira to make those decisions.