Yes it was her during a face-off kind of debate between the two main contenders, and she later won. The female host did supposedly fall over ("doctors are baffled") but it was very strange that although there was a camera on the host a couple of seconds earlier before the switch to the politicians we never saw what actually happened to make her fall.

Liz Truss, the new UK PM, looked very shocked. I don't see this as some kind of "obvious fault" which predicts poor performance as Prime Minister though; I think anyone would be shocked at a surprise like that.

Who knows if it was scripted or not. Another major unknown was that about one second before the off-camera "crash" noise as the host falls over there is a distinct "pop" sound like a wine bottle being opened. That was never fully explained either.