Before we get too crazy here, have we checked for the drum to hub retaining screws yet??? (or whatever they are called) Your drums may have a countersunk screw (or two) that holds the drum to the hub. They are flush with the flat part of the drum where the lug bolts and generally hidden by dirt, crud and dried grime, etc. so clean off the crud with a wire brush until you find them. We all generally use an impact driver to loosen them. Using a screw driver with vicegrips will only booger them up ...
See them in the picture -- next to lug bolts at the top and bottom? I put mine back in place after I removed the drum so I wouldn't lose them.
Look for yours -- they may be contributing to your issue here.
