JazzG Starmer did yesterday and he came out well out of his meeting
He may have come put well in a PR sense but his meeting was a total failure, given the entire purpose of it was to try to persuade Trump to adopt a more moderate position on Ukraine.
Don't disagree with the assessment you posted but the WW3 warning with regards to America offering more support is pretty pejorative. There are any number of ways via any of the three scenarios mentioned that lead to WW3.
Zelenskyy desperately needs to buy time. A humiliating cease fire is probably the only way to do that, save for some curve ball like China involving itself.