Dead bike....

Sounds really obvious but you havent mentioned checking the handlbar kill switch. I expect you / RAC man would have done so. If not check it now, save looking like a giant plumb when the dealer gets it

Other things could be one of the leads to the battery has corroded away. That happened to someone on here. Or the tilt switch hasnt reset since the bike fell over.

Bloody Ktms

I think 9nine0 mentioned that there is a tip-over switch (inside the headlight mask?) that sometimes needs to be reset. I think the idea is that it kills the engine in a crash. I'm speculating and working from faint memory, but maybe that has something to do with it?