[JoeOS14]

It's most likely that the reactor rings on the rear bearings are shot. They replaced the wheel speed sensors unnecessarily. Any good shop would have caught this by visual inspection. You shouldn't have paid until you were satisfied the lights were out. At least you got off cheap.

Your bearings are held in by 4 bolts and yes they are an interference fit to the knuckle. A very common setup these days and the good shops can easily remove them without dismantling anything or using a hydraulic press, unless there is severe corrosion due to road salt. They do them all the time. About $400 per side is fair.

The tire pressure sensor system has nothing to do with the issue,
See also the various Youtube videos if you have the time, tools and patience to do it yourself.