How Do I Make This Mechanism Work?

[Sypherio]

I am creating a diamond generator using an energy condensor surrounded by antimatter relays on 5/6 sides, which are also all surrounded by energy collectors on all possible sides. The open side on the energy condensor is on the bottom. I have a retriever that pulls diamond from the condensor, and that works fine, but I also want to have a chest back at my base (far away from the generator) that sucks up items placed in it to be sent to the energy condensor. When another retriever pulls items from that chest to be converted, the items end up at the tube right under the condensor and are evenly distributed between 4 adjacent energy collectors underneath the relays as well as into the energy condensor. Is there a way to make it only funnel the junk to be recycled directly into the energy condensor while making the other retriever still collect my diamonds?

Ty for reading, please help I also provided some pictures

Problem: Energy Collectors are taking in cobblestone, zombie flesh, and other garbage that I want the Energy Condensor to take in only.