Real Problem or Rip off ?

I am looking for expert opinion on fixing my Sienna problem.

A strange sound is coming from front of the car when driving at 30-45 m/h and more , it is not very loud but my ear can here that.

I came to the dealership and they said it is left bearing and it should be replaced with a hub, But on the top of this they said "Ball Joint separating". My question is what does it mean and how serious this problem ? Should I replace Ball Joints ASAP ?
Is it that I can lose a wheel while driving if it is not fixed ?

BTW.. Bearing issue was confirmed by second shop, but not yet a word for Ball joint issue.

Thanks for your feedback

If the ball joints is failing and is not replaced it could cause anything from increased wear on your tires, to an accident if it fails.

Get a second opinion on the ball joint from a mechanic you trust.