since I was pretty sure I'd killed it by digging up the pupa to photograph, anyway (per your comment on the pupa). At least now I can blame the flies. : )

I have no pinning equipment or expertise, but I'll hang onto these for a while and see if anyone's interested.

I found a lovely drawing of B. bifasciata here. Looks similar but the range listed here doesn't include FL. B. townsendi and some other spp. are listed for here, though. I also found out that they lay eggs on the host plant and the caterpillar eats them.

is a world expert on Tachinids; as he doesn't list bifasciata from FL it's a good bet it doesn't occur there. But then again, these flies move around! I would definitely keep them. No expertise needed, simple kill the flies in a freezer and 'pin' with a fine needle through the thorax just off the center line so as to keep one-half of the thorax intact. Something like this .
Put a label on the needle and keep the flies in a small box with a foam base to hold the needle. Nothing else needed, just keep them dry and don't let cockroaches et al. eat them.