First of all welcome!
You will have to establish your engagement system first.
Look at the front driver side of the front differential. Is there a vacuum diaphragm mounted to the axle tube right by the diff?
Either way I think it is going to be a problem in the differential carrier or pinion bearing.
I'm not sure how the hubs could cause that problem. They will only connect the wheel to the axle or not. If the axle doesn't turn, you have a t-case or differential dilemma.
If it looks like this you have the ADD(automatic differential disconnect) system.
You can also try leaving it in 2 high, putting the frontend on jack stands and seeing if you can turn the front driveshaft by hand or with some channel locks. If so then you can eliminate having a fubar'd differential.