Olde Towne Pet Resort (multiple locations) has suites instead of crates, and if your dog does not do boarder daycamp the staff will give multiple daily walks outside and also multiple cuddle/play sessions. They handled my elderly dog-shy Jack Russell terrier just fine, and I’m sure they will be able to advise on their capacity to care for your dog! The North Bethesda location has a pool where trainers put life vests on the dogs and enter the pool to help the dog swim. Something like that which you can book as part of boarding might be a good way to get exercise without pressure on joints since the dogs are supported by both the life vest and the trainer.