My take on what happened (we are now at step 8):

1. Sam wants to push for more & quicker profit with MS and VC backing, but board resists, constant conflicts
2. Sam aligns with MS, hatch a plan on how to gut OpenAI for its know-how, ppl, and tech, leaving the non-profit part bleeding out in the gutter
3. Sam & MS set a trap: Sam crosses some red lines, maybe taking commercial decisions without board approval. Potentially there was also some whispering in key ears (e.g, Ilya) by seemingly helpful advisors/VCs to push & pull at the same time on both sides
4. Board has enough after Sam doesn’t back down, fires him & other co-founder guy
5. MS and VCs go full attack to discredit board. After some info gathering, they realize they have been utterly fucked
6. Some chaos, quick decision of appointing/replacing ppl, trying to manage the fire, even talking to Sam (btw this might have been a fallback option for MS, that the board reinstates him with more control and guardrails, weakening the power of the non-profit)
7. Sam joins MS, masks are off
8. Employees on the sinking ship revolt, even Ilya realizes he was manipulated/fucked
9. OpenAI dead, key ppl join MS, tech and rest of the company bought for scraps. Non-profit part dead. Capitalist victory

Source: subjective interpretation/deduction based on the available info and my experience working as a management consultant for 10 years (dealing with lot of exec politics, though nothing this serious)