Modifying "Media created" date mp4

Hello, if you open an mp4 file properties in windows file explorer there is "Origin" section with the following fields: Directors, Producers, Writers, Publishers, Content provider, Media created, Encoded by, Author URL, Promotion URL, Copyright.
I am trying to write the "Media created" field and have tried: TDEN, TDOR, TORY, TDRL, TYER, TDRC so far witn no luck.

Any ideas on how it could be done in mp3tag?

ExifTool shows the tag as "EncodingTime".

MP3Tag is obviously not able to handle this "tag", as it does not show it in its extended tag-menue, even if it exists or was created in Windows-Explorer.

What about %encodingtime%?
I see that field in the extended fields list of the filter and also in the list of supported tag fields as TDEN: http://help.mp3tag.de/main_tags.html

I have tried it but what it does it actually creates an additional field "ENCODINGTIME" which is different from "EncodingTime" and no software incl. windows file property system recognizes it.
I also noticed that if I write to "YEAR" using mp3tag it actually writes to "ContentCreateDate" not "Year".

Well, the field TDEN is a V2.4 tag - and Windows does not read V2.4 tags ...
The proper name for a MP4 tag ist WM/EncodingTime. But this should be mapped by MP3tag to %encodingtime%.

So right now I would check if the various experiments with the tags (like creating a V2.4 tag TDEN for an MP4 file) have messed up the tags somehow...