tl;dr:
Order Admins can make changes to orders.
Read-Only Order Admins should be able to search, read order information and Add Comment on the Notes tab.

We have contractors who need to be able to find an order for customer service reasons (i.e. find the tracking number for a shipment, look up the contents of the order for customer support purposes, look at all orders from a particular customer to determine their customer support start/end date for a product). However, they should not be able to change anything about the order other than Add Comment in the Notes tab.

Thank you for your consideration!