When I login to Trello, I see the following url:
https://trello.com/u/r***c*****6/boards
The username "r***c*****6" does not belong to me, so I'm not sure where that is coming from. Interestingly, if I navigate to view my user profile, all of the information there (name, email) is correct.
When I set up my Atlassian account, I set it up as a local Atlassian account - meaning, I do not auth through Google or any other social provider.
In case this helps, when I came here to open a ticket and it listed my products and had me choose one - it listed Trello twice. I'm not sure what the difference is between the two, or if it's related in some way.