I think the DeepMind folks said that they have to get back to London to analyse the case in detail.

somehow, the moves it actually played were ones that would have increased its chances of winning if it was playing itself.

I don't think that's a good explanation. There's no way that removing it's own ko threats with moves like P14 and O11 would have increased it's chances if it would have played against itself.

It look's a bit like belief propagation to update after missing an important move doesn't really work.