Want to update flying on three different AA PNRs going IPT PHL MIA MAD HEL VNO and wanting to check bag from IPT to VNO.

Arrived at IPT and was a brand new (and very nice) what I believe to be a contracted agent. Decided not to push my luck to much, and asked her to route the bag IPT to MAD. She struggled understanding the IB flight from MIA to MAD was a AA codeshare. She called her helpdesk, and after about ten minutes she wrote a manual tag Using AA flight numbers IPT to PHL to MIA, and IB flight number MIA to MAD.

I was worried when I showed up in MAD, my bag may be have been missing. Instead, it was the first off the belt.

Yes, one can get their bag routed on two different PNRs as long as the agent is willing.