what would you do?

If I were in that situation again I would ask for the refund.

I am already having the same situation with a similar camera and the same seller.
This is the first time I have anything from KEH with a problem, they already sent my camera back to me with absolutely no evidence of them fixing the issue even though they did, now the camera went back to KEH a second time and they said they sent it out to someone else.

To be honest I did ask for the repair instead of refund but it seems to be more trouble than it is worth.