OUCH!
It's probably toast.
I had this happen when I tried disassembling one of my Jetbeams. The head is composed of 3 sections: (a) the bezel ring which holds the lens and retainer, (b) the upper head which holds the star above the control ring, and (c) the lower head, below the control ring which holds the driver.
If the upper head and lower head are unscrewed from each other they will torque the driver wires and break them. Before disassembly, it is critical to first desolder the driver wires from the star and then completely remove the driver. It's held in with a screwed in contact plate. In my Jetbeam the upper and lower held were glued with red loctite. A lot of force was required to break the loctite so having it unscrew when trying to change the battery was very unlikely.
When the wires are torqued they break at the driver. The driver itself is a 2-board sandwich. the driver wires actually pass through small holes in the upper board to get to their contact points on the lower board in the middle of the sandwich. When the wires are torqued, they break internally at these tiny pass-throughs in the middle of the sandwich. Even worse, it's almost impossible to replace these wires. A soldering iron won't fit through the pass throughs, so it's not possible to solder fresh wires on, you simply can't get to the contact points. To fix it, you might need to disassemble the sandwich. But doing that would require desoldering multiple SMDs simultaneously
I've modded drivers before, including attaching and removing regulator chips and resistors. But I concluded that the broken driver wires in this driver were well beyond my ability to fix.
Good luck with your repair.
