Adam probably received a call from either Jonah or Rebecca around 4 or 5 Coronado time on Monday afternoon. That would be 6 or 7 Memphis time. He would have made reservations that night to fly out the next morning and then pack. He would have left home early, around 5:30 am Memphis time to head to the airport.
He flies across the country and arrives in San Diego about 3 in the afternoon on Tuesday, 5 pm Memphis time. Rebecca picks him up and drives him to the airport where he went to see Max and Jonah. Max is hooked up to all sorts of machines. Jonah is beside himself with worry. Later, Rebecca comes to pick up Howard and drive him to the airport. Jonah and Adam go to get Jonah out of the ICU room for a little while. When they get back to the hospital, they sit down at the McDonald's for a quick bite, although no one eats much. Rebcecca doesn't say much. After that, Adam and Jonah head back up to Max's room while Rebecca gets the car. She picks up Adam and they head back to the house. It is now 8 pm Coronado time, 10 pm Memphis time. They are both tired and Adam goes into the guest house to go to bed. It has been a long stressful day.
Adam wakes up at 6:30 am the next morning, 8:30 Memphis time. He gets up, makes his bed because he's a good guest, and thinks he will walk down the street and get a double latte and go drink it by the beach. Caffeine and ocean air is what he needs. He will be heading back to the ICU when Rebecca wakes up.
He opens the guest room door...takes a step or two out...
IMO, Adam is innocent. It sounds like he was never even upstairs in the mansion, and I just can't see a murder being planned by him and Jonah during the night. With such a rushed trip, and then being in the ICU, I would think he was exhausted and slept through the night. Just my opinion.