For a long time we have not been offloading the green wfs from ETMY, because doing so would with the same code we use for END X would cause the optic to get a big kick. This morning Jim and I gave this another try, and saw that the main difference between the test masses is that ETMY had some plant inversion from 1-10 Hz, when we turned this off we could offload ETMY without a problem.
Apparently the current arrangement of ETM WFS used durring ALS locking needs these plant inversions to be on.