Looking back on the deliberately-public ambush, I think this has turned out just how Trump wanted.
At first he was talking about swanning in and taking 500 billion dollars worth of stuff as free money under the guise of repayment, but people kept fact-checking him (whether he took that in or just got annoyed is somewhat moot now I think) on the amount spent/given, and then a load of other people started telling him that maybe there wasn't that much in the ground, and it's not so easy as just shovelling it into a wheelbarrow, and the profit doesn't start rolling in for at least a few years, and he was starting to realise it wasn't going to be a rapid money printing exercise.
Then add to that the reality that it could not be a simple surrender-and-hand-over deal but needs a framework first and it's now become far too much effort.
That's when he needed a way out, and up steps Vance - whether prompted or just unable to keep his mouth shut - to be his smug patronising self righteous twit self (helping Trump to escalate and be on a roll).
I see remarks that Zelensky shouldn't have risen to the bait and to an extent I wouldn't necessarily disagree but what the duck is a vice president underling doing having a go at a visiting head of state? This was not some random misunderstanding.
As for Trumps remarks as he was buggering of to play golf for the weekend... WTAF