If I was Isaac, I'd be planning on the transfer portal until/unless I know who the new OC is and they convince me to stick around.
I think it's premature to say he's gone no matter what.
I also think that it would take me some convincing in his shoes - KW isn't known for his capacity to hire OCs.
But if KW were to step down. Scalley were to step up. And then Scalley promised a different approach to offense, while hiring a new OC that matched what he was saying. Someone who was known for innovative offense and/or exciting offense - and the OC told him they want him on the team and described how he will help him to be successful i nthe new offense - I could see him sticking around.