think it could fit, but it will most likely 'deform' the pochette, like make it extra thick and the zipper won't close straight. Compact zipped wallet's thickness is wayyyy thicker than what pochette's, KWIM? I was thinking about getting the 'compact zipped wallet' for pochette too, but after playing around in store, SA helped me get 3 cles instead, which i am much happier. one for keys, one for CC&ID, and one for paper $+coins, make it much easier for me, and more fun as i can clip any cles to my jeans and just go.
Since you mention you wanted the Groom compact zipped wallet, it cost 540, but you can definitely get some cute cles! Groom/Vernis cles runs 200, Damier/Mono Cles runs 150 each, and Perfo Cles runs 215 each, it's much easier for me personally to have 3 separate(3LV vs 1!! lol), and I get to have little bit of different lines, but that's just me. Whatever suits your lifestyle best is what you should go for, have fun!