How to get measured (i.e. from tracking, pre-KF) vertex from hd_root output?

Poking around in output root trees while I wait for MC to run.

(Which, btw, seems like there are some disk slowdowns at the lab and lots of my MC is timing out.  Hitting walltimes of 13+ hrs. for jobs that should only take ~2 hrs.)

I can find the pre- and post-KF K+/beam vertex.  However, it looks like only the post-KF vertex is available for Decaying_Lambda, proton, and muon.

I confess that I don't understand the ChargedHypo branch.  Will keep digging.

MAYBE:

Thrown_X4: contains x4s for all of the thrown particles (makes sense with numbers of tracks, 5600 "events" match with 1400 events that make it through recon)
ChargedHypo_X4_Measured: contains x4s for all measured charged particles.  5177 events.  Distribution looks mostly like the target shape, diminished Lam decay tails... Not sure what's up with this.  Is recon trying to vertex each charged particle with the beam, but then KF gets the vertexing combos right???

Need to ask when the "measured" vertexing is happening for p and mu-.