It's not something you can set up, but we can sure do it for you. OnSemble has the ability to allow a user at an organization to view and edit ALL tickets for that organization – even ones he/she did not open. You just need to open a ticket that says “I’d like to view/edit all tickets” and we can do that!
Also - if you've not already done so - create a login for the Support Center! It is quick and painless, and allows you to have an AWESOME dashboard to view tickets, open tickets, and manage tickets.