Originally Posted by pbarnette

The lowest TPAC TG fares are often in V class, which does not earn mileage, according to CO.com. You need to be very careful with some of the foreign carriers in *A. There are far more partial and zero-credit fares under *A than there were with SkyTeam and the fact that earnings follows the metal makes it a PITA when booking codeshares.

FWIW, it often isn't very expensive to buy up on TG, so it might be worth calling to see about getting credit for that leg.