The opening suggestion seems very naive to me.
If Warnock rallied us to mid-table safety (or better) he would effectively be saying to Nige “There you go. I achieved what you were clearly unable to do. I’m off now so don’t mess it up again “
If we were to continue to descend to relegation under Warnock then Nige would say to him “What have you done? You’ve taken us down and now I’m expected to be a League 1 manager”
You can’t get a win-win for both men.