Home safely and had a great weekend in spite of our issue. Thanks again for the well wishes and feedback.
Bob - I think you're right about the charger converter. Did not meter it but never saw better than 12.5 volts on the panel (normally 13.6 when connected to shore power) after my connection issue and
12 volt accessories saw that drop to 12.1 volts right before we hooked up truck to leave.
Yes, I will certainly be ordering an EMS. Uncertain if I'd do the wired model unless there is great merit here - If I understand correctly, the only thing it may catch beyond a pole-mounted unit is the situation I just had, seems like a narrow possibility for the future. Inherited the surge protector with the coach when I bought it and never replaced it, as I should have, with an EMS. I intend to replace the connector on my 50 amp cable (maybe with Smart Plug, still debating) as the RV shop only had a 50 amp to 30 amp cord in stock that will now serve as my backup.
All my best,
Brenton