How to add name username, user userid from QuickTime SchemeInfo Tags , akID itunesaccounttype atom to extended fields?

i'm trying to add to mp3tag these colums: akID (ITUNESACCOUNTTYPE) but it is missing from extended fields any hints?
other missing fields/tag that i want to add are 'name'|UserName and 'user'| UserID from QuickTime SchemeInfo Tags that according to exiftool documentation aren't writable but i want just to read and dispaly it in one mp3tag column.
from my research i understand that are child atoms of the pinf/sinf atoms and the tag id is 'schi'
someone that can help?
i can read only with exiftools on windows or metarminator on mac.

According to Tag Field Mappings – Mp3tag Documentation there is a iTunes tag called
ITUNESACCOUNT (but no ITUNESACCOUNTTYPE / akID). This tags are valid for *.mp4 only.

If you can't see them in View -> Extended Tags ALT + T, Mp3tag can not read it actually.

thanks @LyricsLover for reply but i want to add akID atoms to extendend field, is the only one that is missing...
akID is itunes account type its a numeric field where 0=iTunes 1=AOL.
'name' is itunes account name (usually is the same of ownr atom) officially it can only be read and not edit
'user' instead is the itunes user id (and maybe itunes user key) it can only be read and not edit and i'm searching a way to show this in one columns of mp3tag (maybe @Florian read here and can help ;-).
I'm not interested in edit it because is drms related but i need only to display it for all my files
About 'userid' i can read it only with one mac app based on avfoundation...