eBay Raw Card Purchases - What's reasonable for a return?

[hypostatic]

I purchased a $500+ raw rookie card recently and just received the package. I don't want to get into the details of the player or card in case the seller is a member here.

The seller had listed two photos of the front of the card in a sleeve and another two of the back of the card in a sleeve. There were no apparent surface issues on the card and I assumed any visible dots and lines were lint and smudges. Fortunately, after gently wiping the card down, all of the dots and lines disappeared and the card looks pristine other than a single "pit" near the center front of the card that wasn't in the pictures and wasn't disclosed.

Based on my inspection, but for that pit, this card might have graded a PSA 9 or 10, but now I'm not sure if it would even get an 8.

Is this something the seller should have disclosed? If so, is this a legitimate reason to return the card? I don't have buyer's remorse. I love the card and I'm happy to keep it for my PC, but I can't help but feel that the issue should have been identified in the description given how prominent it is.