For Poser exported obj files:

I IRC,  Poser OBJ exporter has serious problem in precision of floating point caluculation.
Load simple cube prop from standard Poser library and export it. It's a 5 x 5 x 5 verts cube.
All corner verticies locate exact coordination such as (0.1, 0.1 0).
But second row vertices are (0.08, 0.1, 0) , (0.07999999,0.1,0), (0.08,0.1.0), (0.0799999,0.1,0)..

I'm not sure but if the problem is precision, you can revert symmetry by round off all V line
at 6th or 7th decimal place. I once did that to fine adjust morphed A3 character in Modo.

But it's a old memory, in Poser-6, Modo201 days. Maybe things are changed now.

About original Obj file in geometry folder,  DAZ-A3 is perfectly symmetrical in modo.