There have been pretty solid rumors that we're going to see Galadriel go to Numenor to plead for their aid against Sauron, which is so far from established history as to make a mockery of it.
I highly doubt Amazon forked over 500 million for anything less than full creative control: ie. The ability to ruin the story as much as they want.
...from 2019 that talks about the basic parameters. But, you're right. Who knows? They could make it a real shit show.
But for me, I'm not as invested. I very much enjoy Tolkien's work/worlds, but I LOVE WOT, so I was much more invested in them doing a good job on the latter.
-Samantha Jones, SatC