Imagine if you were the CTO of a company, massively underestimated your AWS bill, and presented your board with something enormous. Maybe something like that happened?
Or, if I wanted to speculate to the extremely negative; what if the training and operating costs ballooned to such a degree, that the deal with Microsoft was an attempt to plug the cash hole without having to go to the board requesting an enormous loan? Because the fact that Copilot (edit: previously known as Bing Chat and Bing Image Creator) is free and ChatGPT (edit: and DALL-E 3) are not should be a red flag...
and
"no longer has confidence"
points to something more serious than underestimating costs.
Of course we have no clue if that's what actually happened. Any conclusions made at this point are complete speculation, and we can't make any conclusions more specific then "this is probably bad news."