By "went out of there way to schedule" do you mean that they had something else planned and dropped it to accomodate you (doubtful) or that they scheduled it for you even though they had a regular checkout coming up. BIG difference. Either way, don't take a chance with an infection. It's just not worth taking a chance.
I had done all the book work for Night, Nav, and Deep (3 certs) and only had checkout dives to do and got a tooth infection and had to cancel when the rest of the class was doing the checkouts. I lost a ton of money (the shop wouldn't let me checkout next time they offered the courses) but made the correct decision. BTW I did eventually do those courses, got AOW and eventually Solo - but NOT with that shop.