Possibly, but you'd have to figure out how to get the 6 strands, and how to cross them. As far as I can tell, with a single strand you need an odd number of strands to be able to have a cord on each side of the pouch. With 6 strands the release and retention cords would be coming out of the same side of the pouch. And if you managed that, you would then have to cross the straps in some way.
 
I would think that it would be better to give up the locked sheep shank idea in a PJ, and simply cut out 4 shorter strands to serve as the warps, and 2 longer strands to serve as the R&R cords, but also have a segment extend into the pouch. You would then weave the straps and cords separate of each other, cross them, and whip/stitch them together.  
 
BTW: have you tried a woven paracord sling yet? It's not a rockman, but it's still a split pouch.

I've done this before.  Whip the exta piece of pouch cord in.