What quantity of oil did the express change place charge out? If that receipt is 3 qts over then he has a leg to stand on.
What repair other than changing oil did the dealer do the first time in? And was it all oil and not fuel or coolant pushing up the level? I have seen stuck injectors fill up a crankcase.
I would think the oil being high would have caused instant issues, so need to look at what occurred 1K after.