They get in before the WCC ever looks at GCU.
Look at their academics and small sports. Just a non Starter all around. Pretty much every single WCC school is elite in at least 1 sport, if not 2-3 (BYU, Pepperdine, Portland, Santa Clara, San Diego, Gonzaga). The GCU is a better fit in the MWC, where they have a lower academic profile and are horrible in the Olympic sports.