Allison... Lmao you can't be serious.. Talk about drivetrain loss..
The 4l80e would obviously be the logical choice. I wonder if your ecm is partly to blame for this? Maybe the wiring is jumbled up somewhere or has an intermittent fault?
The ECM and the wiring harness are two of the few relevant items that haven't been changed out yet. I know he says they've tested as good, but I'd be looking for possible common links between the failures like @miniwally said.



