You may have to disable culling (enableCullingTweaks=false) to make holograms work since they are actually outside the player's view as the entity position is concerned.
So, I have disabled this in config. But there is an "anomaly" on my server. If I at a distance of more than 20 blocks - the Holograms are visible. If I come closer to them - they become invisible. How can I sovlve this problem? I am using Thermos the latest build.