Hi Hive mind, please help point me in the right direction on this. This is a 16 T6 (super / turbo)

1. Ever since I can remember, the car had a "hum" when steering the wheel - enough that when others not familiar that drove the car commented on it. since ~80k miles
2. Car now 130k miles. About 2 weeks ago, vehicle started to squeal. Visual inspection of accessory belt seemed fine, sprayed some water on it, no effect.
3. Opened the breather box and found the faulty PCV flap. Very next day got bank 1 lean code.
4. Very next day, car had sudden loss of steering. Wife was driving, after making a 90 degree turn into a road near our home, she was unable to turn the wheel at all.
5. When I got in, I was able to turn the wheel with a large amount of force - maybe 60-70lbs+, both arms pushing hard - felt like much more than the usual "no power steering" amount, but this is also a heavy vehicle. Lots of resistance, and noticeable notchyness at 15-20 degree turn intervals of the wheel.
6. After limping the car home into the driveway, tried turning the wheel in the driveway - PS would work for about 5-10 degrees in each direction until getting "stuck" and the PS motor would seemingly "force-feedback" the wheel back into place, with lots of commotion and noise. Accessory belt is still intact.
7. Replaced breather box to close out that issue, no effect on steering, and will need to idle the car a while to see if the bank 1 issue comes back.

I'm scheduled to bring the car to an Indy volvo tech in the boston area (Sudbury Volvo) but worry that it's an electronic issue that a local Indy may not be fully read up on. He suggested it may be the intermediate shaft bearing / u-joint on the steering wheel, but that the bearing would create issues every 90 degrees. I'm experiencing every +/- 20. The expensive thing my mind jumps to is PS electric motor failure, or some kind of issue or contamination in the rack.

Anybody experience anything similar? Any thoughts on coincidental issues with squealing / PCV?

I'm fairly mechanically capable and can run diagnostics and perform repairs, but this is my wife's DD so want an expedient solution. The reason I'm here is it took two weeks to get my Indy time slot so it may actually be faster to Forum + DIY solve this.