Watching LinuxTechTips and the woes of getting all the displays working. As to HDMI, it's one display per port and I find folk struggle with drivers and bum cables. HDMI UHD only requires 2.0 cables but I can't guess your setup, cable makes and such.

Anyhow, Display Port is able to connect via one port and daisy to the next displays.

Be aware that your post didn't tell me where the troubles are, but has be recall stories and LinuxTechTips videos of men going bald.