I again carefully cleaned the printhead contacts and the contacts on the carriage three more times.
Carefully drying the contacts before re-seating. I used distilled water and coffee filters tightly wrapped around a flat popsicle stick.
Seems the plastic part around the contacts on the carriage are slightly stained with ink,.... no amount of cleaning removed this. I don't think I can get them any cleaner.
Still the same problem.
HP Tech support wasn't much help.
HP is shipping (should arrive today) a new EG Printhead, since this is the one that initially caused the problem. Hopefully replacing that one will be the solution.
Very Frustrating during a busy season