That's why I asked for the make and model of the old router.
Hughes as a supplier of ISP services is only involved in the "networking" of a customers connection in only one circumstance.
That circumstance being if a customer asks for a router at the time of making their initial service order. That router is a specific model Dlink.
Under those circumstances the router IS being purchased through Hughes, will be supported by Hughes and warranted by Hughes.
In truth many new users don't know the difference between a Modem and a Router. Some may have a Modem with integrated WiFi and wish to reuse that. That being impossible as the Hughes Modem must be used with the Hughes service.
That is possible point of misunderstanding.
The installers themselves as subcontractors only represent Hughes only as far as the work order they have specifies. Anything beyond that is a not Hughes related, that is a business deal between you and that person.
That business that employs that installer is likely to have a number of employees. As in any other field their range of knowledge and experience is going to vary widely.
If a customer orders a router at the time of service order that info is going to be passed on in the work order and the business will send an employee known to have networking knowledge.
If that router is not included in the work order then it is possible that an employee that is certified to install but may not be fully capable of setting up a network is dispatched.