Revenue origin ID is used for some integration connections.
Plans with Affiliates only:
Your Revenue origin ID can be found in the Settings page, under the "Your Trackdesk identifiers" button in the upper right hand corner of the screen.
It is revealed by using the Reveal button.
Access to Revenue Origin ID as Network Client
As network client, each advertiser has a different Revenue origin ID and it can be found on the advertiser detail in the Advertiser list, section Advertiser ID.
Or in the Offer Postback/Integrations section where the Revenue Origin ID is relevant for the tracking, specific of the advertiser owning the offer.