No further detective work needed.
These codes can be found if you head to the discography page within the Distribution section of your RouteNote account.
To find your ISRCs, select ‘View Tracklist‘ within each release so that you can see the ISRCs relating to that release.
See also:
What is an “ISRC” code and how does it work?
What is a UPC and how does it work?
Where can I find my discography?