Integrate with Open Atrium Work tracker Task list view

Hi,

I'm using Time Tracker in combination with Work Tracker of Open Atrium 2.
It works fine, inside a Task.

The thing I am missing is Views integration to a view of type Content:

I'm unable to include Time Tracker fields inside the Open Atrium Work Tracker (Content) View.
=> I tried to add a relationship to Work Tracker fields but they are not available as relationship.
=> I also disabled Views caching to be sure I'm not missing something

I would like to show the total tracked time in the task list View for every task, that would be very nice...