Here's a situation... Not mine exactly but one that's come up recently.
A guy's selling 5 of the same figure, all in a picture together. The description is simply, "You're bidding on the item in the picture". The price is cheap and free shipping, but these aren't overly valuable things. The auction says "5 available", by the way.
So you get the item... Only one figure arrives, instead of the 5 in the picture... Seems like a fishy thing to me. Reportable? Get your $ back?
I did this last year. I sold a little over 100 figures, mostly army builders for damn near $1,000. For a given auction I showed a single photo of, say, all 7 Sandtroopers - then said auction is for one. The auctions had BIN's for $6.99 or $7.99 or $4.99 or whatever the average going rate for a given figure was, had quantity available set to however many I had and were depicted in the photo. I then encouraged people to check my other auctions so they'd buy a bunch of other stuff. Lastly, I had shipping at $3.00 for one figure, $0.50 per figure after that.
All in all I probably sent out around 30 packages with anywhere from 1 to 5 figures in them.
This was around Christmas time of 2013 and of those 30 packages, I had ONE guy who was furious that he didn't get all of the figures shown in the photo, everyone else understood the auctions and left positive feedback without issue. I gathered that he was a parent or grandparent who was buying stuff for a kid and had no idea what the going rates were for this kind of stuff.
I used 7 Sandtroopers @ $6.99 as an example because that was this one guy's issue. He filed a claim and left me negative feedback. I responded to the claim that he clearly hadn't read the auction and that it was unreasonable for him to expect 7 figures that were worth $7.00 each, for $7.00 total.
He responded a few times to my responses, but never escalated the claim to the point where eBay actually has to decide. So I can't tell you how they would have ruled. The negative feedback sat on my record for a year then disappeared from the averages like it's supposed to.
The one thing they said when I called to see if there was any way to remove that feedback, was that since I showed photo with multiple figures, there was a chance they could rule against me if he escalated the claim and they advised me to just wait the 30 days and see if he did so. I think I would have had a good case, but if I do that again at some point, I'll be even more careful to be explicit, and even consider taking 7 photos of the 7 figures, or just using 1 photo and saying you'll get a figure identical to the one in the picture.
Maybe I did a better job describing what I was selling than your guy, but 97% of the people I dealt with understood just fine.