It's a simple answer to those that know, but i'm a bit of a Matrix twit :\
JPCT has a different Y Z axis on a rotation. In an Object3D.getDump().
How would I change it to mirror the YZ value.
My thought was some thing like this.
[0, *-1, *-1, 0]
[*-1, *-1, 0, 0]
[*-1, 0, *-1, 1]
[ 0, 0, 0, 0]
The idea was flipping the values for YZ rotation assuming row major. I think. I've been searching the web so I'm more guessing.
This should do it:
mat.rotateX((float) Math.PI);
well, that's so simple no wonder I missed it. Of course. Rotate along the X by PI that flips both. sigh. No wonder it took a long time for an answer. It was just obvious. :P