I got clarification from a Megatouch guy yesterday. The lock is the factory lock for the Ion, not the Force Ion. The standard cam locks are on the cash boxes, but the CPU locks are cam yet different. He directly recommended against twisting it off as the bottom part(with the "slot") is a cast piece the tab locks into, as it would damage the case. He is sending me a key with the replacement power supply I ordered for another unit. Luckily, he said it's the same key for all Ion CPU locks and can be duped at @ Depot.
Thanks for helping me get to the bottom of it.