It depends how you are running it. If you point flowable-admin to the same instance, then it will show all the data of that engine. How have you set up the applications?
I put the war files separately into the webapps folder. So they are in diff instances :).
Joram, may I suggest that you make a remark in the REST API Getting Started Guide that the flowable-admin is NOT running on the same instance as the REST API’s.
Otherwise, someone new might be caught by surprise that there were no tasks assigned to the managers group even if the holidayRequest process has been deployed and started, because the managers group does not exist in the REST API (there were no instruction to create one).