Trying to get MaxFALL/MaxCLL to be added to 2086 HDR metadata in AME/Premiere

Adobe Media Encode SEEMS to suggest that when you set Content Light Levels (https://helpx.adobe.com/media-encoder/using/export-settings-reference.html#), you would see MaxFALL and MaxCLL. HOWEVER, mediainfo does not report these values as being present in an HDR10 HEVC Main10 L5.1 encode (vs, say, Resolve).

What's the trick?