The option to disable Change Request links in emails is found under the "Changes" tab when creating an event.
In order for the guests to voice their requests, depending on what you, the event manager, prefer, they will need to either contact you via the means you provide or contact the hotel directly. When you disable the change request link, make sure you let the guest know how they can make changes! Remember, you can customize all emails that get sent to the guest with editable text!