Finally solved
Something failed in the e-gas module leading to low voltage output to pin 5 on the e-gas module which leads to pin 14 on the DM. This prevented initiation of codes from DM pin 14, and either as a consequence of the DM not being fully operational or something else related to that circuit in the e-gas module is what caused the ASR/CE and Limp Home mode.

Thanks to all who contributed their ideas on the board and privately and a special thanks to Arthur Dalton for his patience and excellent suggestions throughout a long diagnostic process.

Ultimately not sure still what caused the e-gas module to fail but add this to a long list of ASR fault triggers. Arthur had mentioned that they typically short when a EA goes bad, so wise decision would be to replace them both at the same time. In my case 10 years had passed between EA upgrade and e-gas module failure so I suspect something else caused my failure or the module just gave up. Upon replacing the e-gas with a known good used unit, everything returned to normal and no codes so-far.

__________________
Stable Mates:
1987 300TD 310K mi (Hans)
2008 Jeep Grand Cherokee OM642 165k mi (Benzrokee)