I have no experience with the wedge mouse but perhaps this might help.
I have a Magic Trackpad which paired itself to my MacBook when I wanted it paired to my Windows Machine.
I solved the the issue by unpairing it from the Mac.
I next removed the batteries from the Trackpad.
I restarted the Windows Machine running Windows 8.
I reinstalled the batteries in the Trackpad and then I was able to pair the Trackpad to the Windows Machine easily.
The Windows Machine is not a Mac and obviously isn't running under Bootcamp but it might be worth a try.
Please advise us if you succeed in pairing it to Windows 8 after reinstalling the batteries.
Thanks that worked too! I unpaired the wedge mouse on the OS X Mavericks side. I removed the batteries. I booted back into Windows 8.1, inserted the batteries, hit the bluetooth button on the button until it glows, and succesfully added it via Manage Bluetoothe Devices.
Before the above, I had the same "That didn't work, make sure the device is still discoverable".
Late Model 2012, Mac Mini i7 has a Windows 8.1 Media Center CableCard DVR