Drive axel touches frame? Help!!

i was the first to mention springs. what did the frame shop say about the arch of the springs. if you change them change both sides.

 

The shock bolt in this photo doesn't look straight , or photo taken with wide angle phone lens , bents subjects outside the center.
I know is hard with spending money when you got other priorities with new purchased truck, just a couple of suggestion. This shocks look old, when are like this outside most likely the valving inside is worn out, perhaps leaked oil long ago,, allows damaging road vibrations to shake every bolt ,sensitive AC and electric components.
The frame doesn't look bad, but needs some paint to keep it under control, if rust develops under the huck bolts, around spring hangers, crossmembers, the entire frame gets lose flimsy. I lost the fight with rust on my first truck, in 6 years driving 5-6 months/year on salted roads and ignored the frame. I used twice por15 paint, i read rust bullet and corroseal is also good., on frame no need for sandblasting, just washed the frame with soapy hot water, remove all grease /oil, scrap, wire rush bulged paint rust, and apply it. This primer paints contain phosphoric or tannic acid chemically reacts with rust converting it in an encapsulating layer, needs an extra finisher layer because are sensitive to ultraviolet light. Oil spray it late fall, before the roads get salted, i use spray cans Krown oil on my truck and cars , it takes one hour to do, you'll find all kind of rust preventive oils, WD40 works.

 

after looking all pictures you posted I can say you have ride height problem. You mention the air suspension valve was replaced. Are you 100% sure the valve exactly same as it was before. Volvo uses 100 different styles, sometime the valve looks similar but ports are different. Was the new valve adjusted to keep required ride height ?
Please picture of the air bags from rear. The torsion bar should be in close to horizontal position (parallel to the axle) to keep axle on center. On the picture you posted I see torsion bar is in angle and pushes axle to one side.
Here is PDF manual how to check and adjust

 

I don't think the rear springs are the problem. I have never seen the z type spring with rear mounted bag cause issues unless they break. Granted I am not a volvo guy but several manufacturers use that style spring. They just dont loose their arch like a front leaf will

 

You don't understand how rear suspension is working. Truck air system pressure has nothing to do with rear bags.
Pressure in rear bags in fully loaded 34000 # is about 56-58 psi. I use my dash gauge as scale. Never get wrong adjustment.
You need to check rear suspension leveling valve. Disconnect leveling valve rod and move valve arm by hands. Suspension will rise if you move lever up.
Rear suspension dump switch and solenoid valve, probably suspension in the dumped position all the time.
Check and replace if needed wear pads in spring hangers. It will move front of differentials down slightly.
Don't drive truck in current condition as it will destroy U-joints, differential bearings. In worst case broken out driveshaft with very dangerous and expensive consequences.

 

well what did the shop say