That's a drag. I'm sorry for what happened.
I personally would absolutely have a necropsy done. It would be valuable education, and well worth the money spent to possibly have some answers that might ease your mind. I've had a couple necropsies done, and while none of them were completely clear as to what happened they gave enough info to allow for some general understandings as to whether a death was likely husbandry related, or whether suspected pathogens could be ruled out.
Make sure you're very up front about the entire history of the snake as you know it, and mention all the possible suspicions you have about contributing factors so they can specifically look at evidence of those causes. The more info you give, the more efficiently they're going to be able to confirm or rule out hypotheses.