Refund Help
 

AA made a mistake, had to rebook me on a BA flight, and split my Record Locator. Because of this I can not book my children's seats on a 30 hour trip until 24 hours prior to travel as I would have been able to because of Platinum status. I can however, pay to reserve seats with BA.com at $42 a pop. I would like to do this and bill it to AA for their mistakes since being a platinum member allows advance seat reservation at no cost on international flights.

Any advice would be appreciated.

Do you have the ability to "bill" an airline with any expectation of payment?

You should assume that AA will not refund any monies paid to BA unless they absolutely, positively must under the contract of carriage. If sitting together is worth $42 per seat, then pay the money. If it turns out that AA will refund these charges, so much the better. What I would absolutely NOT do, is pay BA under an assumption that AA will refund the money.