On the potential for blackmail "ending his career immediately": haha, yeah right. If Billy Bush didn't do that, him fooling around with a 17-year old certainly won't.
Nonetheless, the "leverage" theory seems reasonable. It's interesting to note in this context how the Elon feud went: war of words, insults banging back and forth... Then the Epstein card got played, and *swish swish* the whole thing goes away, including Elon's tweet.
My personal theory is less conspiratorial though... I think Trump is more of a "doddering old man" than people think, he's just responsive to people "in the room" or on the phone with him. Various factions have figured out how to leverage that.... C.f. Peter Navarro and Scott Bessent.
In this instance, AIPAC won. They've managed to get Bibi on the phone with him practically every day since this thing began, and Bibi in has been turning the screws day in and day out.