How to get site details authorized by a user during OAuth 2.0 3LO authorization step?

I have created the OAuth 2.0 3LO app in the developer console and have completed the necessary setups that are required to get an access token.
So, Now when I try to get an access token I get the authorization screen by JIRA as below:

In that the user have multiple sites in dropdown and the user need to select one site which he/she want to authorize.
After click on accept button I get the access token.
This access token didn’t have any details regarding the site that was authorized.
And also we get multiple sites if we call API to get accessible-resources using accessible-resources.
We need cloudid to construct URL to get details like list of boards, list of projects etc.
So, How can we get authorized site/cloud id details?

Running into the same problem as described here, Can someone please suggest what is the best solution here ?