Switching modular control rig to FK mode breaks pose of controls that have been baked to rig

From the licensee:
We have built a modular Control Rig in Unreal 5.6, and while IK to FK matching works correctly inthe rig, but we are facing an issue when applying mocap animation to the characters through the Level Sequencer. After baking the animation to our modular Control Rig, the hands and legs IK to FK match switch does not work properly. When switching the hands or legs from IK to FK, the FK controls are moving to incorrect positions and not matching perfectly to IK.

Repro project is [Link Removed]. This issue appears to affect both control transforms after baking to control rig, and also layered control rigs when switching to FK mode.

1. open the repro project
2. Open L_[Link Removed]
3. Open the level sequence that's in the same folder
4. In sequencer, bake the animation to MCR_[Link Removed]
5. Select the global control and set either the right arm or left arm to FK mode
   1. note how the pose of the arm changes
   2. switching back to IK then back to FK improves the pose but it's still not the same as the animated pose