Years ago I requested that WaveLab add the ability to submit masters to Gracenote as well but it seems that Gracenote licensing is fairly expensive unless you’re a big company like Apple.
Maybe things have changed but Gracenote integration in both directions only makes sense for a mastering DAW.
As a workaround, and as proof that it does work, you could configure your local network’s DNS so that the name freedb.freedb.org resolves to the IP address of gnudb.gnudb.org.
Yeah, I configured my local DNS server to resolve freedb to gnudb, so Wavelab (any other software) connect to that one automatically. Works like a charm.