Trump has apparently declared war on the Republican House Freedom Caucus. Basically, it appears he is saying get on board or he will cooperate with the Democrats.
Ironically, Trump's base and the HFC base are pretty much the same people.
And it seems Chris Christie's problems just got worse. He is now "working" for Trump as chair of a commission on opioid abuse in US. He will be working for Jared Kushner's new organization in the White House. That should be interesting.
Re' your last point: Yes, Christie put Kushner's daddy in prison when Christie was an Attorney General and now Christie will be reporting to son Jared. Awkward!