Ah sorry should have been more detailed.
Use an Add Data Element to create a "Reference Type" object of "Group". This lets you pick from a dropdown of Reference Types.
Add the permissions like the above post, set to "All Users", this will change next.
The Tick the "Override Reference Type And ID With Variables"
Map your ReferenceId which is the GroupId you have got from SQL or whatnot,
Reference Type is the Group one you created earlier.
Set your SessionId.
(This is done in "SD.IncidentManagementSimple" within the Model: "List Group Names In Queue")