The one staff role with a login: your own schedule, your own pay, the stage plots, and covering for each other.
Bar, floor, door and security are cost records with no login. Sound engineers are the exception and get an account, because unlike everyone else on that list they need to see what is coming and what it needs.
You can be on the roster of several venues, and your shifts across all of them appear in one schedule.
You never see the act's fee, another engineer's rate, or anything from the settlement side. Your own pay is the only number on the page.
An open cover request does not show the rate. Until somebody takes it, it is still another person's recorded pay — which means you decide on the night rather than on the number.
Taking cover does not need the owner's approval, and the shift keeps the rate it was created with. You are both on the roster because the owner put you there, so they have already said either of you may work the room — and a swap between engineers must never change what the venue agreed the night would cost.