Just to make sure, that I understood right: You have hardware with an installed UCS and connected a Wifi USB adapter to the hardware. Now you want to connect to WLan via the USB Wlan stick as a networkcard.
I think you first would need to make sure, that the USB Stick is properly acknowledged and the acknowledged as a network adapter. So: is the WLan USB networkcard acknowledged in UCS (does UCS "know" it has a networkcard)? Second you need some way to use the WLan stick to discover WLans and connect to them - I do not know if UCS has that abilty out-of-the-box but there should be tools that let you do that.
Though, I would recommend to connect via networkcable.