Campaign creation with advertiser ID?

We are looking to create campaigns via the API and have run into an issue with the API documentation.

https://developers.taboola.com/backstage-api/reference#create-a-campaign

We would like to be able to set the advertiser ID for the campaign during the creation process, but there appears to be no field listed for it.

The call would be to https://backstage.taboola.com/backstage/api/1.0/account_id/campaigns/ but I suspect we have to use our main account ID in that URL. then later provide the advertiser ID that lives within our account?

It would be awesome if the documentation could be updated at some point to mention things like this, as there are a lot of blind spots in what it covers.

Under "Campaign Fields" there is advertiser_id but it is listed as read-only.

Also, is there an API call that will return all advertiser IDs for an account?

Thanks!

/Chris