Circuit not working: Differential impedance, or skew, or a different problem responsible?
Start with nice earth grounded end 0V points high quality cable, CM chokes for cable,  to avoid SMPS CM issues getting into differential signals.

Then read about group delay distortion from abrupt changes in trace thickness, skew and lack of impedance controlled FR4 electrical test and how eye patterns get closed.

https://link.springer.com/referenceworkentry/10.1007%2F978-3-319-14346-0_41 

I have a nicely designed HDMI port on a good  8core i8 ASUS tower that gets sparklies on video porttions to a 1080p big screen until I put my finger over the CM choke. So much for automated connection Group Delay equalization  routine....routine or left out??  BUt if I get a real high quality shielded HDMI short cable its clean. 3 others various noise lefts. Any cable kinks it get permanently worse.  This is also running at similar speeds to your test.

The feedthru caps I think should be the ideal low ESL X2Y types only.