Looks like you don't know much about lnx2mac and his driver. He is violating the GPL deliberately for several years because he took Realtek's linux driver and warped some code around it to make it run on OS X. As the original linux driver was published under the GPL, the derived work falls under the GPL too, making it mandatory to provide the sources to anybody (at least on request) who received a binary copy of his driver, but he doesn't. He is stealing from the open source community and he has the impudence to ask for donations on his homepage. Besides, he did an awful job, maybe that's the reason why he's keeping the sources secret.
According to the level of support the tonymac staff has given him, he must have a really close relationship with those people. Try to criticize his behavior or his work over there in the tonymac forum and you'll see for yourself.