The Soldiers at Northwatch may use conjured weapons or flames but the only wizard there is the Northwatch Interrogator who may possibly be perm if anchored since he does not respawn.
The problem with him is that his level is radiant 14-50 which means a narrow chance of a thrallable but also powerful minion.
Suggest a save before starting Northwatch in event he can`t be thralled first try.
Since Sonja is at level 31 , I decided to raid Northwatch without the rescue quest to see what`s there.
There were indeed 2 unnamed Thalmor Wizards inside , the first could be raised by Revenant , the second one by Dread Zombie.
But the Northwatch Interrogator resisted Dread Zombie and was thrallable !
The entire remainder of the Keep`s Thalmor were all under lvl 30 and were turned to Ash Piles.
I loaded all the Glass/Elven weapons and Elven armor into the Interrogator and went To Whiterun to sell my loot.
After leaving the Skyforge , I realized Sonja had never visited Jorvassgr and stopped by to see what the Companions were doing.
Upon entering the longhouse , a fist fight was happening between Athis and Njada .
I watched them for a bit until Athis took a knee.
Njada hit him a couple of more times , stopped , and sat down at table.
Athis then took out his sword and slew her !
No one in the room reacted to this and Njada didn`t draw her blade.
So I got a lvl 25 thrall for merely entering the place !
In the necromancy trade , we call this " Buy one , get one free "