Move decomposition after splitting submeshes?

[SkytAsul]

Hello!
I am having a little trouble converting a composite OBJ file representing a hand to an MJCF file.
Here is the result after running it with obj2mjcf --obj-dir . --verbose --save-mjcf --decompose:
(group 2 visual)

(group 3 collisions)

You can see that at many places, the convex hulls stretch across multiple submeshes (for instance, the two last phalanges of the pinky, annular and middle fingers).
This makes the addition of joints between the submeshes impossible.
I wonder if it wouldn't be nice to move the "decomposition" step after the splitting in submeshes?
Maybe I am completely missing something about this util...
Thanks for any help