Hey AweSam, I'm sorry for the predicament you find yourself in! I actually fully understand, because I have two pet rabbits myself. My one rabbit is 11, so I know we could not put her through either the flight or quarantine. My other rabbit would likely be fine, but I have come to the conclusion it would just be too stressful on her. It's heartbreaking since I love them dearly, but my mum is able to take them in and give them just as good a home as they have with me.
It sounds like your situation is unique, though, in that your rabbit has free reign of your house all day long. I don't think it would be impossible for you to find someone willing to give Hodor that same life, but it would certainly be difficult. I would recommend talking to a rabbit-savvy vet about the options. Some of the facilities used for quarantine look quite nice; have you looked through the list of authorized premises? The list is available on uk.gov: newcomer link: https://www.gov.uk/government/publications/rabies-quarantine-authorised-premises-and-carriers/rabies-quarantine-authorised-premises-and-carriers [nonactive]
Since some of the facilities do look quite nice (especially 4Paws in Lancashire!) my main concern would be the trip itself. Again, I think the best next step would be talking to a vet. Maybe you can give Hodor some medicine to help him relax during the flight and make sure there are no layovers to ensure the shortest travel time.
Best of luck, keep us posted with how everything goes!