They did notify everyone. They did it after firing which is within their rights. They may also choose to stay silent if there is legitimate reason for it such as making the reasons known may harm the organization even more. This is speculation obviously.
In any case they didn't omit doing anything they need to and they didn't exercise a power they didn't have. The end result is that the board they choose will be impotent at the moment, for sure.
All this proved is that you can't take a major action that is deeply unpopular with employees, without consulting them, and expect to still have a functioning organization. This should be obvious, but it apparently never crossed the board's mind.