Bought a MSD 8534 off a member here ( see Photo of what I got)

I would love to. But He will just leave a untrue negative on me, right?
He might. I 'm not familiar enough with how that works but at least you are able to help others not get shorted. Yes those deposits are strange looking. If he doesn't refund your money you might have to try to clean the thing up. Is the stuff loose? Could you blow it off with compressed air?