Alright I used the inf wizard utility that comes with the lib-usb download. As long as I force the kindle to be in usb recovery mode it makes and installs the correct driver.
I adopted the flashing instructions from the noob guide (as well as copying the img file back over) and did the whole n-u-z-x thing and the kindle displays as usb ethernet/rndis gadget. Unfortunately I CANNOT set the IP address, despite the fact that it correctly appears as a network adapter in Windows devices manager. There is a "netword address" field which doesn't allow the full address that the noob guide wanted, but trying a shorter address I can't ssh into the kindle (using putty).
So that is where I am at now-- I have it up to the kindle acts like a network adapter but I can't set the ip address nor can I ssh in.