He's trying to kill us--could ruin him--worry about that later--grab your sister and go.
"Almost certainly not. Well, is there anything wizards mostly can't do that I might be able to?"
"Nope and don't even know what that means. Damn. There's probably something, but--oh. Hm. I could de-age people, I think I saw enough old people that that's not redundant, at least."
"Oh! Yeah, wizards don't do that. You probably want a big commercial caster office with a huge network and maybe you can work something out where they call up their big customers and have you de-age them and then you can get a translation spell and a scry for your sister and a call or summon depending."
"I'm going to want to figure out something longer-term at some point, once I find my sister, assuming I can't just teleport us back home. Which I will want to try, but this is completely unprecedented as far as I know."
"If the identifying characteristic is hair color I'm not sure why the word you picked in my language was dragon. Dragons are supposed to be usually-large reptiles that may or may not have wings or breathe fire."