Not sure I have heard of this problem before, but if the machine still runs with the brushroll removed, then yes the switch is jammed. Unplug it of course, and get an air duster and electrical contact cleaner and blow it out then clean it with the contact cleaner and stick a small screwdriver in there and fiddle with the switch and manipulate it. If that doesn't fix it, then yes you would need to replace the switch.
More often than not they get dirt buildup in there and it jams the switch up. I have a Kirby Heritage II that someone said didn't work and the motor was dead. Turned out the safety switch was just stuck from rust and some contact cleaner and then poking it with a screwdriver and loosening it up fixed it.