The data is certainly noisy, but with a reasonable moving average it is discernible which antenna is receiving a stronger signal over the other. It is much easier to tell with a larger angle between the antennas which is to be expected.
Indoor Relay Tests
I conduced a simple indoor test by leaving the “UAV” transmitter in my room, walking down the hall into a friends room where I could no longer receive signal directly from the “UAV,” then set up the relay right outside his room in the hallway and switched my “ground station” receiver over to receive from the relay. The signal was relayed perfectly.