No, that's correct. In order to join the Levels Class you need to be a current member of the Raw Class.
You're right to choose "no".
Then on the next page, you have to choose "Yes, I've taken it in the past, and now I'd like a refresher."
Soft-proofing should be the solution, actually.
But it relies on the labs providing you with a super-accurate soft-proofing profile. Crossing my fingers!
They literally print it this size, then cut off the extra 3mm all around. It's standard printing procedure.
If you don't provide that size, they'll enlarge your file, then print then cut. So you'll lose the edges of your photos that you want to keep. That's why you need to give them the extra.