Maxos was a Dragon Knight, I'm 99.(9)% sure. It's indicated many times, besides why would he NOT take the gift of being a Dragon Knight? He wanted wisdom and nothing more, and through becoming a DK he has got a little part of wisdom of Dragons.
What if that kind of knowledge make him to forget his human memory? He was looking for knowledge, so I'm not sure he would be ready to forget anything. Besides, he maybe didn't need dragon wisdow to be wiser than them, if dragons respected him so much.
