I was wrong - it's a ferrite bead, not a fuse, but in this case it may have acted as a fuse. If this ferrite bead broke down (melted) and opened, stopping the flow of current, then everything past it might still be OK. While I understand completely that Aquacomputer cannot recommend doing this, what have you got to lose? You can solder a short piece of wire across the terminals then apply power to the Quadro. Don't connect any fans or USB or LEDs. If it smokes, then OK it's dead. If it seems ok, try connecting a fan. If that seems OK, try connecting the USB and see if it shows up in Aquasuite. I would have the USB plug into a hub instead of straight into the mobo. The worst that could happen is you damage the Quadro further, and maybe but not likely, a test fan, or the USB hub. My guess is it will either work or just sit there dead. I really doubt anything will catch on fire or be damaged.
The alternative is to say OK bad luck and lesson learned. When in doubt about a custom cable, verify it with a meter before plugging things in. Good luck and If you fix it, let us know!