I need to go by what your saying. I assume she was facing you? I know this is a Tom but it wouldn't be different for a hen, minus the beard and slightly smaller stature.
It's obvious since she ran off you didn't snap or cut the spinal cord and likely not the spine at all. Knowing that, you couldn't have hit her "square" middle of the chest because you wouldn't have been able to miss the spine. If she was turned in the slightest you could slip a broadhead past the spine. What we also have to remember is how small the bird is under all those feathers. The impact through the chest meat could easily knock here down and even stun her and still not actually kill her. Perhaps the arrow passed between her body cavity and wings resulting in extreme blood. The vitals as you can see are lower than you think on an upright bird.
My shear guess is that you flesh wounded her but even if you did indeed kill her (I don't know how much blood was actually on the ground), turkeys have a tendency to bury themselves in leaves/brush etc.. Like deer, they are hearty animals.
I'm sorry about the recovery BHF, that's a tough one and it's possible she's alive. If your familiar with the area, she'll probably turn up one way or another. I don't know if any of that helped but the daigram may be of some assistance.