There is no reason to think about using an AAV.
Cut off all that junk you have in there and install a P-trap.
It looks to me there is room room to do this, despite that it will take away from the storage space in the cabinet.
The proper thing to do it open the wall and raise the level of the tee in the wall.
Is this
I WANT-TO-BE-A-PLUMBER TOUGH LOVE SESSION?
You connected the drain system the "hard" way by using glued sch. 40 PVC.
You should have seen what I cut out. I reasoned the SCH 40 would be a better system than the thin wall tubing used previously (it even sported two separate traps).
You also made it difficult to revise it because the tee at the wall may not have enough pipe available to cut the tee off and install a different fitting.
Actually, there is a PVC adapter at the wall that screws into a CI 90 degree bend so tear out is no problem.
Your real problem is that you believe the guys at Home Depot when they tell you all you need is " a few fittings and our advice".
There are no sales people at my area box stores that actually speak English so I buy @ a plumbing supply store. Much easier and cheaper. I actually draw what little knowledge I have from HARRY HOME OWNER TEXTS.
As an aside, plastic threads do NOT like metal slip nuts.
I had no idea. That will be remedied. I just didn't like the look of the plastic slip nut. CHARLOTTE actually sold this setup so I ass-u-med it was OK.
cacher_chick found my actual flaw, I was concerned about taking up storage space. I certainly do not wish to remove the counter top to slide the cabinet out. I will re-plumb with a P.
I just hate the look of that thin gauge tubing and am actually concerned it could become damaged with storage under the sink. He doesn't want to go the cost of metal tubing.
Now that I have been corrected, is there available a sanitary tee (SCH 40) with a diverter inside or should the GD discharge (right hand sink) be lower on the left sink drain (now do-able as replacing with a P-TRAP and lowering assembly)?
Again, Many Thanx!