Ragdoll distortion on first update

Hi Everyone,
I have two boxers fighting each other.
There’s a short screenshot video here:
video

I have modified KinematicRagdollControl to detect bone collisions between the boxers. When a boxer punches the other, the punched boxer goes into ragdoll mode for a duration. Future plans will see the boxer return from ragdoll mode in many ways, but for know he just blends back. I haven’t changed any ragdoll code, just the collision detection, so the ragDollUpdate algorithms remain untainted.

Well it all works except for one problem. After entering ragdoll mode, for the first update frame only, the boxer gets totally corrupted. See screenshot below.
Corrupted model
This is apparent often but not always, but if it’s a single frame problem, maybe the screen update misses it sometimes…

I turned on the debug skeletons, and there doesn’t seem to be any corruption in the PhysicsRigidBodys (meshes), or the bulletAppstate skeleton (green arrows), just the model skeletons (thick red and blue bones).

I’ve tried many things, stared long and hard at the code etc. I am lost. I don’t understand why the bulletAppState debug skeleton never looks distorted, just the model.

Any help appreciated!
Thanks,
Tom.

Screenshots and videos: