Ok, you've replaced the hub again-- with the rotor off, the hub is rotating freely, no tight spots and no looseness? Just making sure.. If no, get back into the hub and fire your buddy..lol
If yes.. I'd suggest taking the pads out, reinstalling the caliper and finding a way to hold the rotor tight to the hub (maybe some pipe over 2 opposite side studs and put a lugnut on each stud to clamp it a little). Make sure the rotor turns squarely to the caliper frame, quiet and with no runout.
If ok, then we're on to the rotor/pad contact. Reload pads and pump brake pedal to seat the pads. Does it get hard to rotate after applying brake pedal? Do the pads pull back from the rotor after applying pedal? With free pistons and a sealed hydraulic system, the pads should pull back This may take a buddy to push the pedal.
Id also look inside the wheel to make sure theres no witness marks from some contact.
