After a new alternator, battery separator and three batteries.. more vehicle death.
When it occurs, clicking turnover sounds stop and then nothing, not even remote key fob. Battery cables were checked and rechecked at service centers. The battery shows good charge.
Finally, a roadside assistant with Progressive showed me the loose (again) positive battery cable but also a bungled side mount battery receptor. Either different people have overtightened three different batteries or something goes on while driving a heavy vehicle. I will chase this down this week and hope for the best.