First thanks for including what year and plant your car was built at. It would also help if we knew when it was built also - either projected (from door tag) or real one from a Marti report
It's great that your documenting what you find now
It looks like to me that on the front Wheel wells that the bare steel was painted with body colour paint (in my case Dark Moss Green) and that it was painted from the door posts all the way through the wheel wells to the front radiator support area.
Very unusual and unlike what was typically done. Exterior color would not have attached itself very well to bare steel - so surprised it hasn't chipped, cracked or fallen off in those areas you believe were not applied over a base of primer sealer. Must ask - are you sure about this statement? Your pictures don't show areas where you sanded through the paint layers to determine application order. Just some scrapped areas where the seam sealer was. If no primer stuck to the bottom of that section of sealer could you provide a picture of that ?
Then it looks like Sound Deadener was applied over that quite heavily from below the cowl area through to the front radiator support. I have removed a lot of the sound deadener to discover what lies beneath it.
Not unusual for some applications to be heavier than others - are you sure its all sound deadener or could it be a combination of sound deadener and undercoating. very common for dealers or owners to have the cars undercoated in most regions of the US and other countries. Must say I've seen much heavier applications of factory sound deadener - I see not buildup on the upper edge where the fender would attach not at the front splash shield
Also I read that the sound deadener was applied after the coil springs had been installed. Looking at my image of the inside of the shock tower I cant see how this could have been done as there is a lot of sound deadener in the shock tower also under where the coil spring cover would prevent it getting sound deadener up there..
Just no other place in the factory for it to be applied other than where it was scheduled. Not like the plumbing, wands and shields were moveable or portable. Since they did spray from below the car a generous worker could have gotten the wand above and behind the shield but it would be a first for me. Now a worker applying undercoat often got it everywhere - and in corners and pockets the factory never considered. Thing that is a good possibility here
1. the sound deadener needs to be applied BEFORE the coil springs are installed
2. that I 1st need to paint the area from the door posts through to the front radiator support in Dark Moss green
3. that the Dark moss green should not have any primer underneath it?
Think I already address #1
#2 is just a choice of the painter. Can find examples from every plant where a painter went a little crazy and painted forward allot more than usual. You car is just one of those. Of course this paint gets applied when your painting the rest of the car as originally done
#3 Would not follow what was usually done and not sure that you've confirmed that by stripping through each layer in front of the shock tower, in the shock tower, behind the shock tower, exterior surface for the cowl (front or side) to conform this. And you'll need to do both sides. In fact since it appears to be allot of body color no one would ever see that surface and most every painter would suggest to you apply a primer sealer so that you don't have problems with your top coat later. Just don't think that is what you'll find on both sides in all those areas
Must mention - it does look like there is black paint over the green on the forward panel and on the frame rail. Is that PO added rattle can or factory black?
The "sound deadener" or what ever it is in the shock tower pocket does not look like factory stuff. But of course these are just pictures which can sometimes mislead since they are only show two dimensional surfaces
Let us know how you investigation goes and what you discover next