I know that he will get a big paycheck if he is sacked, but being publicly dragged by the press for almost two weeks now, probably does not fell good, and I think INEOS could've and should've dealt better with Ten Hag internally.
Imagine having a new CEO coming into the job, and not give you one single shred of reassurance for months about your position, while talking to other people than can take over your job tomorrow?
Even if he stays, which I seriously doubt that it will happen, there will always be that sour taste in the mouth that INEOS does not believe in him, which will likely be backed by not giving him a new contract.