The Lifeguard, the Maracyn that is in a bottle (Maracyn Oxy or Maracyn Plus?), and the Tetracycline can go for sure. You can probably return the Melafix as well. There is some controversy about whether or not these two "fix" meds actually do damage the labyrinth organ; I'm inclined to believe they are only damaging if they are overdosed. They are helpful for topical issues but will not do anything if another fish is struck with whatever took Angel.
That leaves the Maracyn and the Fungus Clear.
I guess that makes some sense about the testing labs, as I think it is a bit labor intensive to do a complete necropsy. But that's too bad. :( Maybe send to where Coppermoon sent hers? Basement Bettas also sent in a fish, I believe. Not sure.
EDIT: Want more ramshorns? :D