If Charles is doing an ECDL, he should have done an initial test to see what level he is at. There's absolutely no reason why he shouldn't do the tests if he already knows the subject. Tell him to ask to do a practice test.

As for the digital photography, it may be that there aren't enough takers to run the course. It's immensely irritating. I want to do a digital video editing course, but there are only about 3 other people who enrolled and the minimum we can run the course with is 9.