SpawnDefaultController do that, spawn the default (AIController) and possess.
I try that too, unfortunately the kill order is given in all events after close client/leave/network error i try, the early its EndViewTarget if i remember right.
I check and the player character its possessed by the AIController, but its destroyed anyway.
That a good idea if exist any other event called before the engine do the kill pawn order and was one of my first try 