Hey there @filipem welcome to the community!
I apologize for the delayed response on this one but was combing through our backlog and wanted to respond - Where exactly did you land with this? Were you using the Google enterprise connection or standard social connection?
For future reference, the sub claim should look something like google-apps|117686103243408785895170 rather than using the user’s email. It looks like an issue was fixed at some point where the mapping did point to the email rather than an id.
The complaint was that the email may be too “brittle” - In this particular case either should’ve worked, but perhaps the internal id may have been a slightly better option. The sub claim is now improved to include an id as mentioned previously.
Hope this helps!