the dongle I got with my WS2812 had a VendorID of 'test device', the reserved Vendor ID 6666 (and device ID 5555) which is never supposed to be used in production. it reports itself to be a generic HID (human input device) and has no special drivers, only the generic windows HID driver (hidclass.sys, hidparse.sys, hidusb.sys, and hid.dll), at least as far as I can see.
first make sure your 2812's display panel is synchronizing with the weather instruments, then do the HW Resynchronize, down arrow til it beeps, push the sync button on the HW program, a few seconds later, the console should beep again, and a few more seconds Heavy Weather should display your data.
heavyweather talks to it via the generic HID device interface in Windows. I started to play with a USB snoop program and grabbed a 30 second sample of the protocol, but I haven't taken that any farther