Here's what you need to read to set it up.
http://line6.com/media/support/toneporthelp/GearBox2_TonePortUX2_Footswitch_Control_Rev01.pdf
I'm not sure whether that footswitch will work or not. The footswitch inputs are looking for a Tip/Sleeve connector connected to an On/Off switch. You have two footswitches conncted to a Tip/Ring/Sleeve connector. Having said that, I believe that is to a Peavy Rockmaster (I have one) and is worth trying. It will only switch one thing but I think there will be enough of a connection that one of the switches will work but only one. I'm pretty sure you won't get both fooswitches to work.
Wait, I just had an idea. Try using an adaptor. Female 1/4" Tip/Ring/Sleeve to two Male 1/4" Tip/Sleeve connectors. Something like this
http://www.ebay.com/itm/Hosa-1-4-TRS-Female-Dual-1-4-Mono-Male-Adapter-YP-136-Stereo-Breakout-Cable-/330896928860
I'll bet if you connbect both male TS connectors to both of the UX2's footswitch inputs, they will act like two seperate switches. Try it. I'm very sure you can't hurt anything.