It seems very clear he realised how bad it would look if he was wrong and pushed his source hard for confirmations. It also seems clear he rates his source and makes it sound like it's at a pretty senior level.

So, the obvious scenarios are a). source was mistaken. The stressing of confirmations seems to indicate it couldn't really be a mistake.

Or, b). the source misled Pepe for some reason or someone misled the source who in turn passed it on.

So I think the main question is what reason would someone have for leaking this knowing it was false?

One scenario would be, as Dan noted and as was mentioned on the original X thread, that it had appeared in the Israeli press as a potential response so maybe this is intended to discourage them from actually going ahead with it by showing how it could easily spiral out of control and getting everyone else lined up against it.

I'm not sure what a "physics analysis" of what may or may not have happened is going to help.