Sorry to hear about your problems. I've encountered my shared of problems too with fish delivery. From bullheads, to dead fish, to sick fish. That's one of the reasons why this forum is so valuable. Helps to sort through all of the reasons and solutions.
That said, what exactly would be your concern with the dead coon in the other pond? I don't know how big their ponds were, but dead mammals in ponds certainly don't help the water quality any. But I'm having a hard time visualizing how that would equate to a problem with your pond. I'd guess any bacteria present in the pond of origination would be fairly ubiquitous species.
