Here's a guess I'll pose. If I'm right and Rupert wanted to make the donation to Dominion and likely the DNC as well with the 787.5 million hit.IN doing so he got a taste of just how tough it is "to pretend to win a big suit" like that when all the judges and juries have been pre-spiked.
Bearing that in mind and realizing that tucker was so good there is no way they would not have to defend him sooner or sooner they chose to get rid of him.In doing so they didn't have to pay money to someone that they didn't pick in the first place.
Sounds logical. Plus they don’t want to risk any more truth telling. I guess they don’t mind bleed viewers.