Is it possible to drive a car 50 miles with a bad lower control arm

How old are the brakes? Sounds like you might be down to the wear indicators. They make a vibration at first and then start to squeal if you let them go longer.

Long time ago I had an idler arm go bad that started with a vibration when the brakes were applied. It was a drum brake car and one side grabbed just a bit earlier than the other and resulted in the vibration.