Ive seen it in an airplane engine, yes. Car/buggy engine - no. A bent crank would be fairly easy to see when running - the clutchbell and flywheel would wobble a little bit. It would likely be visible if it’s bqd enough to make the front bearing shield to oval out and come out. I would be removing both bearings and checking them over carefully and take your crank to someone that can chuck it up and run a dial indicator across it to determine if it has any runout. Maybe it’s not the crank - maybe it was the rear bearing the whole time? Is the engine under warranty?