Turning it into an emergency and surprise coup with innuendo of wrongdoing looks to have been a huge mistake, and may result in total loss of control where a more measured course correction could have succeeded.
It does not matter that the board has the legal power to do whatever they want eg fire the CEO. If the investors and key employees that keep the company going walk away, they end up with nothing so they might as well resign and preserve the organization rather than burn the whole thing down.