The solution was to set the AVR's input hdmi port to "4k enhanced" instead of "8k enhanced". I'm not sure why that was the solution, but once I did that libreelec recognized the hdr capabilities of the tv again.
HDR was working flawlessly a while ago, I'm unsure what changed. I know I ripped a new bluray and tried to play it back but HDR wouldn't work. Below is a log of when I was trying to playback another movie that worked previously. Is there anything I'm missing? Thanks for your help