the return pump will kill the pods, but that's not the only benefit of a fuge. If you want it for the pods, having it on the sump is not a good idea, but if you want it to remove organics, then having it on the fuge would work.
I have my fuge below my main tank and my return pump kills some pods/mysis but most are unharmed. Should be fine on your fuge if you don't have room on the back of your display.