Their argument citing that case is pretty weak. In that case, Publisher's International published a book about the TV show Twin Peaks, after the show came out. A very in-depth book citing plots, actors, dialogue, etc. Although Publisher's International didn't have copies of the script, they did copy basically the TV show after it came out. In this case it would be very hard to prove that the website had any such access, especially since the Walking Dead show has not come out yet. They probably haven't even registered their copyright. Plus it is obviously commentary on the show. However these days the one with the deepest pocket wins in court, sadly.