Hi
In your Remote Desktop Session Hosts can you enumerate the print drivers that is present ? To see it click on a printer, and in the top bar you will see print server property.
You fail to tell us if the user can still see those printer in their session, please share more input on the problem.
If the driver is not present please reinstlal it, and if the users can't see the printqueue, make sure the printer is there, installed on a local port, and that the security on it is set for them to use it.
Thanks