What if the crank bolt wasn't tightened enough. I'd bet you could get enough movement to confuse the CPS and get a randon misfire if the balancer was loose. The balancer will wallow out from rocking before the crank, killing the balancer. I'd try a new balancer only for starters.

I'd be considering if the stealer did a crappy job of torquing down the crank bolt, which is not easy, and can break the damper all by itself. Which is why if I can't get a flywheel locker, I "torque" the crank bolt down with a 4lb deadblow hammer on the wrench. None of mine ever came loose or broke...