2006 Honda Accord EX Coupe 2.4L Manual Transmission.

Thank you for your time...including detail in case there are clues.

First potential symptom was intermittent check engine light (solid, but not always on). First breakdown rpm's drop to 500, no power for 5-10 seconds, engine quits. Cranks, but won't start, green key flashing (immobilizer). Tow it to a mechanic. Mechanic baffled...no codes but no real communication with car either. Doesn't know what to do, pokes around a little, car starts. Drive it for a few more days, then on the highway, full/instant engine cutoff. Coast to stop. Cranks, won't start, green key flashing. Push it a bit, it starts. Drive it home and park it. Next day, drive it to mechanic, drives fine, turn it off. Won't start for mechanic. Locksmith comes to try to communicate with immobilizer, etc., can't get anything from the ECM or immobilizer (via his computer). We check keys, relays, ignition coil, still no start. Mechanic gives up, I tow it home. Still cranks but won't start. Rather than give up, I decide to buy a used ECM to see what happens. Remove old ECM and notice evidence of damage in connector E (pictured). New ECM comes, I install it, locksmith comes and does relearn, car starts. Driving now a couple of days, no issues, no codes.

Does this seem like a failed/bad ECM and I should just smile and drive, or a short /bad ground that fried the ECM likely to happen again that I should try to track down?

From ECM picture, the problem was potentially in vicinity of Connector E, pins 19, 20, 21, 29, 30 (I think 31 is empty)