Lol, Gothams are completely irrelevant when it comes to Oscars. Each of their awards is determined by really tiny juries (for ex, the Breakthrough Actor prize was chosen by a jury of 4 people), which lends itself to more idiosyncratic predictions.
I think they pretty much just choose what they want -- they definitely don't try to predict the Oscars (which is admirable). In 2009 and 2010, Jeremy Renner and Jennifer Lawrence lost the Breakthrough Awards to complete unknowns each time who had zero Oscar buzz. Even last year, Felicity Jones defeated Shailene Woodley and Elizabeth Olsen, both of whom had more Oscar buzz than Jones did. Basically, the Gothams do what they want. And they are not apologizing for it.