I do think the move to 8chan probably coincided with at least one ARG-jacking. The 4chan "trip code" thing Q was using on 4chan is a joke security-wise but the move to 8chan had no hand-off at all. There was no way to have any assurance it was the same person. (Again not that 4chan is secure.)
A real "high-level informant" with "Q clearance" would have used a f'ing PGP signature or a signed message in a Bitcoin transaction or something cryptographically verifiable.
Edit: the white-hat coup narrative goes back really far in conspiranoid and new-age literature. It goes back at least to the I AM movement, which had a narrative that sounded a lot like Q plus some ascended master woo woo. I AM was a totalitarian cult with fascist-adjacent leanings that was at one point trying to organize a march on Washington, but it never happened for some reason. I think the cult leader died or something if I remember correctly.
There's a tiny bit of evidence for a direct link. There was a video making the rounds a while back of Michael Flynn at some Q event saying a prayer that turned out to be straight out of one of the I AM offshoots. Seems a bit of a stretch though to imagine some old cult trying to launch their revolution a second time. It's more likely that grifters are just pulling bullshit from places like I AM to develop their own grifts.