HDR with custom Premiere Pro Exporter

I'm developing a custom Premiere Pro exporter in C++ using the Premiere Pro 22.0 C++ SDK on Windows and would like to support exporting HDR sequences (i.e. Rec. 2100 HLG). Unfortunately there is not much HDR documentation or guides on how to properly do this.

Especially the ADBEExportColorSpace parameter in the Common Params identifiers list looks interesting to me. But it isn't anywhere documented in the SDK, nor do I know the values or datatypes it accepts.

Does anyone have more knowlege in this, or know how to hide warning messages like 

"Source color space ( Rec. 2100 HLG ) cannot be exported by the currently selected format. Export color space ( Rec. 709 ) will be used instead." or how to solve this?

Or is this information considered as non-public and would require me to sign an NDA?

Thanks.

(Moderators: Please delete my crosspost.) DONE