High10 + HDR turns out darker.

So I have this high quality project, I thought it'd be looking nice on youtube to have the 1440p + HDR option, the only problem is that whenever I press High10 + HDR and render it, it takes longer time and the end result is almost 75% as bright as the original version of the video. It's for a song made by Zella Day & Vanic, the high quality is crucial for everything to be noticeable. I'll be uploading the videos, one with HDR and one without.

The One With HDR:

This is the one with no HDR:

My media encoder settings are:

Everything is edited in 32bit color depth. 
So is there any reason why it's so dark?