The problem I have is IB express flights count for OW credit on AA, but not VY. IB does sell higher fare tickets on VY that earn miles in IAG programs (also have a free checked bag), so I don't see why the fares would not be considered strong enough for programs like AA to be able to award miles.
The issue is it is hard to avoid VY flights as many routes that might used to be IB are now only available via VY.
Rasheed