Hemi Continues to quit at Speed.

Just to clarify on the coils shorting out.

The hemi engine valve covers have rubber isolated bolts and if the coil secondary of any coil shorts out against the valve cover it goes to the path of least resistance which can be a nearby harness and spikes into the pcm and will cause a symptom like you explained.
It shuts down the pcm and stalls the engine and then is fine on a restart.
I have heard of guys just start replacing components , sensors ,pcm, etc , and still have same problem because the ground straps are broke, or in the case of an engine swap missing.

I looked at a 04 ram in the shop and it had a ground strap on the valve cover bolt that loops from the top of the bolt back around the rubber to the base of the bolt so if it the coils short out it will shoot the secondary voltage back into the head/block ground.

Might be worth a shot to run a ground for a test. One on each valve cover.