To update.. here is an email I received after contacting Rewards Network:

"Hi Mr. XXX,


This email is to advised that the 1500 miles that didn’t get transmitted to the airline has been set to be resent. The airline liason advised they should receive it within the next 4 weeks and then will be posted to your frequent flyer account within 2 to 3 weeks after that. I will keep an eye on your account to confirm it is sent.

Please let me know if there is anything else I need to provide. "

Lovely.