Proposed class - Armed/unarmed combat. Magic isn't his first language, (he isn't Jasper after all) so Hendrik would teach people how to fight without their wand if it's lost or stolen. He still has his armor and can show folks how hand to hand combat works. And if he gets his hand on a sword or a wooden weapon or even a shield, that can be taught too.

You can take the knight out of the kingdom, but you can't take the kingdom out of the knight.

Or something along those lines.