Her description, quoted from a Wired article which she has re-tweeted (which I interpret as an endorsement) is as follows:
"Tuesday Gebru emailed back offering a deal: If she received a full explanation of what happened, and the research team met with management to agree on a process for fair handling of future research, she would remove her name from the paper. If not, she would arrange to depart the company at a later date, leaving her free to publish the paper without the company’s affiliation."
I read that as an explicit ultimatum.
https://www.wired.com/story/prominent-ai-ethics-researcher-s...