Blender animation merging

I am trying to create a fully linked flying control run for a experimental aircraft project.

My problem is I have flaperons that operate from the same differential plate.

I created NLA tracks for “Aileron” and “Flap_Deploy” custom animation code using IK armatures. Individually they work perfectly (In sim) but when merged together some of the parented objects float away from their pivot points…

Is there any specific export options or anything I might be missing?

If more info is required please let me know.

Many thanks.