Hi,
If google translate has done it's job then I think I have a very similar setup to the one you are trying to get working.
I have a 1.2m offset dish, on which I have the Bullseye LNB and an IceConeFeed helix antenna.
My RX Path is from the LNB, 1.5m of coax to a bias tee, from there it feeds into RX port 1 on a Pluto plus.
My TX Path is from the TX1 port of the Pluto plus to an Analog Devices CN-0417 pre-amp. That boosts the output of the PlutoPlus to a level that will drive the 12w DX Patrol Power Amp. The power Amp is then linked to the helix by 1.2m of low loss coax.
My shack is about 15m from the PlutoPlus and the dish so I have a 15m length of Cat6 ethernet cable plugged into the ethernet port on the PlutoPlus and the other end plugged into an ethernet hub in my shack, or it can be connected to the computer via a USB to Ethernet adapter.
I control it from my computer using SDRConsole software.
It sounds like you are not getting any TX or RX from the Pluto back to the computer via ethernet cable is that correct?
Regards. Mark - G1INU