Aye, I was a bit

on that switch. I liked the old male Sorceror model. They move it from only he can have a Chariot, to he says there can be no male Sorcerors, seemed odd that they need to have a restriction, but I suppose it represents Malekith is a bit of a paranoid maniac, who's blind to the fact his mother will off him the first time he actually becomes a real problem to her.
As to using your own, nothing stopping you, just say he is a renegade male caster working for your general. At the end of the day, a Male could survive by keeping his head down, staying outside the Naggaroth domain, or having a powerful House deny his presence.
One of the better options would have an army themed around working from a Black Ark, as out there on the open seas, Malekith's wants and fears mean didddly squat to a ambitious Captain. If the male sorceror is doing a job of note, then who is he to judge.
If you have a female sorceror in there as well, and folks start bugging on about how there is no way she would work with him. Just break out the siblings excuse. Works everytime.