If that model supports it you need the USB A-A cable it came with and it has to be plugged into the Main USB port, usually labeled as U1 or Main or Master. The other port won't work. Also, your Pandora's Box should be off/unplugged otherwise.
Hopefully it didn't damage the Evercade cart. A Game Boy cart slot provides 5v on pin1. Evercade carts being SD cards expect DAT2 on pin1 and only need 3.3v on their power pin. Both carts have a ground on the last pin. (Evercade carts actually...