I agree with most of the guys posting up for ya that there really isn't a shop around that will take care of this problem. There are so many factors that contribute and only so much time a shop is willing to put into a job before they simply give up or tell you that you have to start all over and dump a fortune with them.
I've never looked into Planman's checklist but it sounds like a great write up and I would def read it over for better understanding of what to check and how to check it.
Trackbars and wheels/tires do seem to be the primary culprit, then down the line of failed or failing parts lists of each related component. We see so many rigs that have gone through and replaced everything just to have the parts go bad very quickly due to getting beat to shit by the dw.
I've personally been pretty lucky and never experienced dw on my rig. Of course I am so anal about checking all the steering components very regularly and servicing them as needed or replacing them if there is the slightest amount of play or slop that maybe by sheer dumb luck I stay just ahead of the curve. lol.
Yes, your pics suck. Don't know how any of us could help with such unclear pics. Good eye to those who can
haha. So all the steering components are RE as well, including the trackbar, draglink and tie rod you are running?
I do see that you have a dropped frame trackbar bracket along with a RSP sector shaft brace. I will assume that when the dropped tb bracket was installed along with the RSP ssb it was set up custom and that no stress was put on the sector shaft or gearbox itself. Not that this would affect dw, but rather it would affect your sector shaft and gearbox over time (this is completely off the subject so sorry, just checking for ya). I'm not a huge fan of the front frame side drop bracket. Yes it gives more clearance for the use of any tb especially with the RSP ssb but it also allows for some flex that might be avoided a little better by raising the tb at the axle side instead (Artec makes a great one -no I'm not a dealer or anything like that, just like their weld on mount).
Again, off subject a little, but important to the equation. How much caster was built into your PR44? Typical PR44 setting is 6 deg with the pinion at zero which is pretty much the same as a stock rubicon d44. You say 4wheel parts told you that your caster is set at 4deg? Seems a little low to me on a RE 3.5" lift unless you have some heavy ass bumpers and winch gear and the lift has sagged out really bad. By seeing the clearances on your dl flip and the dropped tb bracket I would say sagging isn't the case. You only have a couple degrees of pinion angle which seems pretty low to me too (am I the only one). I doubt you have a PR44 with 10 deg of preset caster though but check on that so you know which PR44 you do have.
Check the caster yourself and don't rely on 4wheel parts. Use a large socket and place it on the upper ball joint with a digital angle finder. This will help you to set your own caster/pinion angles and also get you working on your own alignment and get the jeep out of the shop. Anyway, I recommend starting at 5.5 deg if not even a little stronger and work from there positive or negative depending on how YOUR rig responds to it. Also note that both sides may not be the same due to mounting brackets possibly being mounted in slightly different positions on either side (both axle and frame). In other words, your control arms may not be the same lengths. Very common and nothing to worry about as long as the axle is perpendicular to the frame to begin with and positioned properly front to back. Once axle position is set using the lower arms, the upper arms will just fall in where they fall in at whatever caster or pinion angle you ultimately decide on. Upper arms can be off as much as 1/2" easily although not commonly that much, but rare that they are exact on each side. Avoid the desire to twist the axle to make them the same length and know that both sides of caster may not be exact. Also avoid adjusting the lower arms to compensate as this begins to put your axle at an opposing angle which then starts to put wear on components and will result in a pull to one side or the other...
I don't want to bad mouth any manufacturer but RE joints can sometimes tend to wear very prematurely so def check out the control arm joints. Good thing is that if they are bad, RE should replace the joints for free. If you had your rig at 4wheel parts then they should have already checked them. Now, with that said, it's very likely that they didn't so put that burden on yourself too. Once you determine that the control arms are holding the axle in the correct position, you can then start diagnosing other problems. Changing the tires out is a great starting point to determine if they are the culprit or not. If you still experience dw then start at the trackbar like most folks are saying, bushings or joints, mounting holes and bolts. Even slight wear can contribute. Seems like the quality of our tre's these days leaves a lot to be desired so really check and double check them. Again, even the slightest amount of play can multiply during a dw experience. Ball joints add a lot to the equation as well so don't ignore them.
Death wobble is a nightmare and due to all the factors involved, it can take time to diagnose. But if you rule out tires then it should be much easier. Get the rig down to some of the guys offering to look at it and have them help you learn how to align it yourself. The more familiar you get with it and the more regularly you maintain it the less likely you are to have issues and the happier you will be. Nothing can be more frustrating than chasing an illusive problem and that's why we are all here, to help each other out. Good luck man!!