Regardless of TSA packing, if ample water, a bit extra, was provided, they actually did their job. It would be as simple as taking package to car, looking in said package, identify a heating pack, and removing. 100% not necessary in climate controlled environment, acros would have been fine @70F no problem. Seems like the miss was treating a hand carried live package vs. shipped, 2 different scenarios. Somewhere, there was a breakdown of communication between OP and TSA.
I am still fuzzy on how exactly this happened, cause the buyer, 100% made some critical errors. The OP could have requested a larger Styrofoam shipping package for fish, put a gallon or 2 of water, then float purchased frags. Put lid on, call it a day. The extra water leaving store at 78F, with bagged purchases, controlled at 70F, give me a break, no way they would have died from cold water. I have had acros delivered in 65F water, no color loss, pe within the hour upon placement in tank. Especially hardy, well grown corals, they are quite resilient, but above 86F things begin to head the wrong direction. I would have ditched the heating pack myself. Glad everyone is happy, great customer service TSA, any replacement or reimbursement was above and beyond!
Cheers