Jeez, make the prints already. If they don't want them, chock it up to the CODB.
To the rest- Restocking fee? Nonrefundable deposit? for an 8x10?
I have had this happen to me before and there ended up being a lot of 000's at the end. Why would anyone buy something they couldn't see first? A lot of bad advice here. Worst case scenario, you have the prints to sell to someone else. Go ahead and do it.