[X] Place the Bracelet of Mandatory Co-operation on the corpse's wrist, then use Limited Wish to cast Raise Dead to resurrect him. Then continue as you previously intended to before accidentally killing him
[X] Place the Bracelet of Mandatory Co-operation on the corpse's wrist, continue as if Coil was still alive (teleport back to base?), then use Limited Wish to cast Raise Dead to resurrect him, continuing as previously planned afterwards.
-[X] If he refuses to be revived, use Speak with Dead to retrieve information about his bank accounts and what you'd need to authorize things, then transform into him and pretend to be him for the moment.
[X] Roll with it. Pretend you intended to do that the entire time if anyone else asks.
-[X] Disintegrate the body and get rid of the costume as well. No evidence.
-[X] Cast Discern Location to make sure we got him instead of some duplicate (who knows what Parahuman Powers can do) to be safe