A threaded axle is needed if the hub has cup & cone bearings, to set the bearing adjustment. Wheels/hubs that use cartridge bearings can easily do w/o the threads, as yours does. See the small, smooth, stump of thick pipe in the center of your hub? That's your axle. It'll work just fine together with a q/r.



Well, you're gonna need something. If you can't accept a regular q/r, or one of those tool-operated skewers, then the only option left is a new axle.
And the question is if replacing with a threaded/nutted axle is at all doable. I don't know enough about aerospoke to be able to answer that offhand.
Depending on axle, "locknut" and bearing dimensions it can be anything from fairly straightforward to something requiring custom fabrication of support sleeves, spacers, and maybe even bearing replacement.