Hardware questions about Xbox Hori Wireless Tekken stick

So a friend and I are building our own arcade cab for fun, and after some research, we’ve found the Wireless Tekken Hori stick was actually one of the cheapest options for us. It’s a shame we’re tethering a wireless stick, but 'eh.
My question is, can the stick run off 5V, or does it require the 3V that AA batteries provide? It would be nice if it could run off straight 5V, as I could plug power in via USB or something similar (maybe off PSU, who knows?), and save effort in dropping a 5V line to 3V.
A second question, does anyone know what the four pins behind the AA battery holder do? Since I’m taking apart the stick, I’m considering whether I should just chop off the wires coming out of the harness, since if it’s not of any use, why keep it? Is it for programming or other maintenance work on the circuitry? Anything that might be useful? Thanks in advance, much appreciated. ???

No one with any advice? =[

I can’t speak for others, but I’ve never dealt with one. If you had good pics of the top and bottom of the main board, maybe I could figure something out about the power or the four wires, but otherwise, nah, got nuthin’.