The tcase and hubs have no interlock between them. One can work without the other. However, the tcase and the hubs must both work correctly to transfer pulling power to the front wheels.
In this case, the tcase not working will never send power to the front axle, no matter what condition the hubs are in (locked or unlocked). If the hubs are locked in without the tcase working, you will be turning the front axle/wheels/driveline with power from the rear wheels transferred through the ground. This wastes torque from the rear turning excess front end mass.
If the tcase works correctly, then the front axle will spin if the hubs are not locked in (unused power, which turns everything except the wheels), but will transfer power to the wheels if the hubs are locked (pulling power).
Manual hubs mean you must get out of the truck to lock the hubs in or take them out. That is the operational difference.