Thanks Bud. It was a shot in the dark, but I had to ask. If the door alarm (VTSS) was really at fault, there would be all kinds of noise and lights flashing... which you don't have.
I'm leaning pretty heavily toward the PCM at this point as being your problem. It doesn't fit perfectly because I'd expect it to die while driving at least occasionally. But all you have is a no-crank no-start every once in a while. WITH NO CODES.
The loss of the TPS code is one of the major reasons I'm going this way right now. It would be nice to know if the fuel pump humms for a second at key-on and what the PCI voltage is while the van is disabled/ down. But loss of communication alone should cheese off the PCM enough to have it set codes of its own, including SKIM transponder key codes. The PCM almost has to be asleep during these times.
The good news is that it should be covered free of charge under the extended 8 years, 80,000 mile Federal emission warranty. The trick will be convincing your local Dodge dealer to replace it for you based on what we've seen here. They may insist on seeing the van act up and getting a positive diagnosis before releasing a (rather expensive) PCM and we both know the trick is getting the van to act up!
New thought. There was a recall a few years ago for PCM connectors having problems with water intrusion. The weatherpack was getting bunched up during installation on the PCM and might provide the avenue for water entry. In the right place, water could short across circuits and possibly take the bus down or something similar. I don't remember the exact year for the recall, but it's right around the same as your van.
The PCM lives in a rather inhospitable place, just below and to the rear of the left headlamp. If you lie on the ground and slide under the front skirt of the van you will see it tucked up just behind the left wheel well splash shield. I don't know how much you can tell from there, but the recall involved looking at the connectors (4 in all) to see if weatherpack was bunched up in the release tab area. This is the top of the connector, the side you can't see without a mirror.
If you decide to pull the connectors off for inspection, there is a red slide-lock that must be pulled outward from the PCM direction. Then the black thumb release tab will click when pressed and the connector will come off. Be prepared for plenty of road crud in the eyes (lol)!
The recall had us replacing the connector(s) as required if the weather pack was damaged or if there was green groties-type of corrosion within the socket. In the case of groties, it got a new controller.
Regardless (at this point) of whether the recall applied to your van or not, check it out for weather-tightness. A garden hose shot might be the trick... it's off the normal underhood area, so hosing this spot won't affect anything else. It gets a fair amount of road spray while driving, too.
If the bus got shorted to voltage while driving, the SKIM system wouldn't be activated until the next key cycle, either. The engine won't die while driving once SKIM has given the OK to start on the last key cycle. If the loss of bus communication isn't noticed, the next attempt to start will be when the no-start will show up.
Finally... maybe something that makes some sense. It's not perfect either, Bud, but maybe you can help me out here!