My predictions for who dies (NOT SPOILERS, just THEORIES)

UM, No. You're wrong. Legally, they cannot use characters under property license while they are in the middle of a deal that requires regulatory approval.

I don't know what you mean by bringing up the Shwarma scene. That comment seems like a non sequitur. Yes that was filmed at the last minute as a joke, but all of the characters in that scene were owned by Marvel. They don't own the X-Men characters. They are currently still owned by Fox and they can't use them until a few things happen.

1.) The deal goes through (again, that won't happen until Summer of 2019)
(and in the meantime, another media group doesn't swoop in to make a sweeter offer, like Comcast)
2.) The deal is approved by the government (after Summer of 2019)
3.) The current X-Men universe films are completed and released (meaning New Mutants and Dark Phoenix), effectively concluding that franchise. (They may also want to work out whether or not they would continue or conclude the two TV series that are still ongoing, meaning The Gifted and Legion)

Even when they finally used Spider-Man in Civil War, the previous Sony franchise had concluded and their deal specifically involved sharing the rights of the character with Marvel. But Sony still owns him. That was a completely different deal from the current one. And it was a deal that had been signed and gone through all the proper legal rigmarole before he made it into the movie.