The rams will have a chip on their shoulders from reading that the cowboys have all the momentum coming into this game. Therefore the chip on your shoulders motivation might negate the cowboys momentum.
Then because half of their stadium is filled with cowboys fans, theyll feel like they are playing in an hostile environment which will psychologically provide them an edge.
Not wanting to be upset by the underdog cowboys gives them further motivation.
Now if it comes down to it, the rams might want this game more because they are playing in their home city and that home cooking might give them a slight edge and nobody wants to lose at home


Also mcvay will not want to be out coached by Garrett because that would be an embarrassment so that would negate any peychological edge that Austin might have trying to show up his old team.