That's not how it works. There are no restrictions on who you can work for, even if you were a CO/COR. The restriction is on representating a firm to the government. This happens very frequently; it's seldom that a flag officer retires without multiple offers from industry.

""" it might be assumed that a former contracting officer representative could not be hired by the same company whose contract they oversaw as a federal employee. Even though seeking such employment while still in federal service would represent a prohibited conflict of interest, seeking and being hired after federal service ends would be allowed ... the rules would bar the employee from representing them, such as through a communication or appearance, before a federal employee regarding the specific contract he or she oversaw """ https://www.army.mil/article/194019/moving_to_private_sector...