Agreed. Just because etrailer's tech support people weren't there that day doesn't mean that they're gone forever. Try again.
Of course they will probably refer you to Lippert's support because they have never seen that issue either. Since you have already called Lippert, you can arrange a return and refund from etrailer while you're on the phone with them.
Odds are you have some oddball budget spring bars with undersize u-bolts.
Again, this would have been best served by starting a new thread. You already got deltabravo.