Thanks, in that case we don't need to create other users right? It's all controlled by the encoded parameters?
That would work perfectly. Is it possible to do this without authentication though?
As it seems a bit unnecessary to have to sort out all the DNS issues for the managed Looker instance, just to set the one cookie to load the embed correctly.
If we're willing to assume that the security of the encoded URL is enough (since if the third-party shares the URL, they could also just share any authentication, etc. anyway) - then the result is the same, the user opens the URL and sees the resulting dashboard without authenticating directly.
But having to create a page for the embedding on our own server, with a script to set the cookie first, etc. is a lot more work.