I have some of those special connectors required to parallel dewalt packs, and I'm working on building the pack.
What I gathered is the connection from the BMS unit to the cells is what needs to be parallelized.
The way I'm approaching this is ... I bought some 5-conductor wire (it's 5 22 gauge wires in a plastic sheath). I've built six cables with the special connector on one end, and ring lugs on the other end. The ring lugs are wired to a 10 connector terminal strip that I'm using to implement the parallel connections.
Where I'm stuck is the connector coming from the BMS. The connection at the BMS end appears to be this same special connector .. but.. it's thoroughly potted in place and I can't get it to come out. So.. hmm, curious.
I can't tell from pictures others have posted how y'all handled this. If I can't get that connector to come loose, then the only thing I can think of is to cut the wires coming from the BMS and splice some of the 5-conductor wire. The BMS obviously needs to connect with my terminal strip. I'd expected to just pull out the connector, and connect the BMS that way.