I don’t know you and it seemed that you were getting some things mixed up. Just wanted to be helpful. To keep it simple:
1 Make custom profiles of your camera, screen and printer, keeping in mind the editing and target surround and media. Other profiles to consider would be noise, white level and lens profiles. Approach could be simple or advanced; however, doing it vs not doing it makes a big difference.
2 Do colour management. Your OS, CMS, apps, screen and video card must work in tandem; otherwise, it fails. In a simple workflow, you have a raw processor, raster editor and image viewer. All of these must do colour management internally and constantly communicate up and down the system the proper dynamic range, bit depth and gamut for accurate display.
3 In dt, choose a suitable working profile. This one is up for debate. I would choose a well-behaved profile. See: The Quest for Good Color - 1. Spectral Sensitivity Functions (SSFs) and Camera Profiles and Elle Stone's well-behaved ICC profiles and code. And I would choose a colour space that is slightly larger than your output profile to give room for processing the pipeline but not too much as to make the gamut compression difficult. dt 3.0.2 has the following:
4 Choose an appropriate output profile for your output file. The list is almost the same as the working profile list. Notice you have some interesting options such as PQ Rec2020, which I am guessing is linear Rec2020 with a PQ OETF. You would have to check what kind of PQ it is. HLG is simpler because it is designed to work with SD and HD displays; it is backwards compatible.
Anyway, have had lots of insomnia, so maybe I am getting it wrong or thinking one thing and writing something entirely different. Smarter and clearer minded people are bound to join the conversation. In fact, I see one of them typing already. 