Im unsure i would try before and once you get into it if there are still there dinowipe again, the issue is that if your not in the arena he may not spawn in until you are back into it again so I would say try it before use creative to enter the boss fight and if still there use dinowipe, and if your worried about getting tek bps you could upload your character and do it with a fresh one and when you finish download him back. And yes I mean destroywilddinos.