Why Are "source_url" and "source_zip" Not Returned for Playable Ads via Facebook Marketing API?

I’m working with the Facebook Marketing API to analyze playable ads. While querying playable content, I only get access to two fields: "id" and "name"

I noticed that some SDKs (python) reference fields like source_url and source_zip. But even using that doesn't give me the source.

Here’s what I’ve done so far:

GET /v21.0/{ad_account_id}/adplayables ?fields=id,name,source_url,source_zip &access_token=<ACCESS_TOKEN> 

The above call only returns a list of playable assets with only the id and the name fields. No source fields

My Questions:

1. Are the source_url and source_zip fields supported in the current API version?
2. If not, is there any alternative way to retrieve the HTML source files for playable ads?
3. Are there specific permissions or configurations required to access these fields, even as a page admin?