As usual, unfortunately, DxO hasn’t finished rewriting the user guide. The current user guide for PhotoLab 6 is outdated when it comes to the linear DNG export options:
Exporting images – PhotoLab Guidelines (dxo.com)
I think we can assume that the “Export to DNG (Denoise and optical corrections only)” option is unchanged. The only other option makes it clear that when applying all corrections the Color Rendering options are never applied. Reading DxO’s documentation on linear DNG workflows (including the PL6 user guide - see for example #10 on the page I linked to), I get the impression that the new exclusion of color rendering is to ensure that nothing non-linear is written to the linear DNG output. So no color space info, no color profiles…
People were having problems with using PhotoLab 5’s linear DNG output in Adobe software. For example:
Maybe this is a correction. Would be nice to hear from DxO about this, but maybe this helps in the meantime?