Could you tell me the detailed model number of these three devices?

Tried Ethernet backhaul in a new installation tonight and it failed. The AP Deco started reshooting as soon as we plugged the Ethernet cable in. The cable previously worked for a homegrown wifi extended setup, but further digging revealed that it only has 4 wires connected, not all 8. Still, Ethernet should work across it I would think. It used to. No?

Just bought a tripple pack of D5s, just to find out that the needed ethernet backhaul isnt working for me. Why?????

setup is:
floor: modem = router1 = d5 n1

2nd floor: (router1)=switch=d5 n2

My first attempt to set up Ethernet backhaul failed. The process of adding the second Deco unit hung at some point after it was recognized. It was at one of those steps that was supposed to take less than a minute, and gave up after 15. Then I was able to connect it with the Ethernet disconnected. Should I just plug in the Ethernet cable and hope that it helps? How do I tell that the backhaul is working. Are there tools that would accurately measure the difference in Wifi speed?

Ethernet backhaul not working here either. Latest update on all Deco's.