I'm sorry to hear this. The construction work could've caused him a lot of stress and this may have caused him to just stop eating. My cat Ziggy became so stressed out from a plumber and my parents coming over to my place, going to the groomers for a lion cut, and then going to the vets for her annual exam that she then stopped eating. They didn't all happen in the same day but were spaced out over about a month's time. She was diagnosed with pancreatitis and had to be later hospitalized for 24 hours.

My vet also specializes in cats so I would definitely try to get your inlaws to take Max to the vet that you've recommended. She can have all of Max's info faxed over so that the same tests aren't repeated again. It's critical that a cat eats something or else they can get fatty liver disease and very jaundiced. My Ziggy ended up being able to eat on her when she returned home but I had to give her vitamin B-12 shots once a week for about 6-8 weeks. This helped to stimulate her appetite. She's been fine ever since and gained all of her weight back and then some. Lots of prayers and positive thoughts are being sent to Max. Please continue to keep us updated about him.