Hi Drew,
The images you show may not show the alignment results well. I recommend you open two afni controllers, one with the anatomy and one with the overlay from case 1. See how well the cross-hairs correspond to the same location.
Try again with the results of case 2 and see if, after placing the cross hairs on the same location in case 1's anatomical, the corresponding location on the epi is different.
Having said all this, do me a favor and try WARPDRIVE_MATVEC_INV_ instead of ..._MATVEC_FOR_ .
cheers,
ziad