Pico crumble recharge port

Hello,
i just finished my first stunt saber and want to build a fx Version with pico crumble now.

Im not sure if the recharge port is wired correctly. Why does it Need two negatives (one soundboard and one battery)? Something to do with the kill plug? Below is my wiring Diagramm (edited from Plecter manual). I would be pleased if you could take a look at the picture and tell me if the recharge port is wired correctly.

Attachment 16247

Thanks in advance and have a nice day.

/Edit:
Okay i think i made a mistake, the direct Connection between the battery and soundboard must be invalid. Right?

Your edit is correct. You need to remove the direct connection from the battery to the soundboard.

The rest of your diagram appears correct.