Huge company doesn't mean they can just continue like that, a stable coin usually need a huge funding to reserve and if facebook is about to do that themselves I don't think the coin will be as big as if the partner is still willingly to invest into this coin.
The news about all these partners dropping out or withdrawing themselves from the project itself is already a huge bad news for the future of the project and you can still think about how the loss of money will definitely affect the project.