Unfortunately an aggressive ball python is something keepers will run into. I know I have a fair few myself.
As for the deformed tail... how deformed are we talking about. If it is at the very tip of the tail then I think it should be alright. It may have been broken at some point or it could be born with it. Its bot really a fact more of a suspicion that a snake born deformed will produce deformed babies. I haven't tested it myself but I am not so sure this is true.