I think Cummings will survive this, in the sense that he will keep his job.
But I think it's the end of the road for him too. The idea that he was a political savant was always based on uncertain foundations. He was an arsehole, a 'nonconformist' and a man who was tolerated as long as you could believe his own proclamations about how smart he was. The abrasiveness, the outsider status, and the divisiveness were part of a personal brand that only works if people believe you that you're a step ahead.
All of that has been massively exposed over the past few days, he's been exposed as a spoofer who's making it up as he goes along, who's a prick because he's a prick not because he's special and who has no more of the answers than anyone else.
He only works if he's in the shadows avoiding scrutiny, he'll spend the rest of his days in Downing Street as an increasingly isolated joke figure and be ousted for the next rising star bullshit artist when the Tories think it's safe to do so.