Game Boy With Pi 3

[bpempire86]

So I tried posting this on Dirty Bullets Pi 3 thread in show off corner but it wouldn't post, so I decided to start a new thread to ask my question. This is what I posted:

Hello there, new to the forums. I started with the pi zero project but decided to divert to this halfway through, so got a pi 3 model b. Got a bunch of games working for ps1 sega etc. Had pretty much everything wired up and working ok. Have an issue now though...

Got to the part where I had to remove components from the pi 3 and even then everything was fine. Removed the two USB, ethernet, and display ribbon ports and after soldering my USB hub I still had working controls. After that I took my Dremel and cut off part of the pi board as suggested - the part where the two USB ports and ethernet jack used to be. However now I cant use controls or keyboard. Swapped hub with a single USB port but it still doesn't work.

Did some probing around. The ground pins still had continuity to ground on GPIO header. 5V however did not, so I gave the USB port 5V by another means. Kept green and white wires where USB port was and tested again, but controls still don't work.

Not sure what I did wrong. I cut exactly where I was supposed to. I guess my question is, is there another spot on the pi 3 board that I can hook up to get USB working or do I need to purchase another pi 3?