*Spoiler* The motel owner?
I take it the motel owner is Aidan's future self.
shareActually, it was his present self. He was old because he had to live throughout the years from the time he went to the past when his grandparents were younger. Remember, he was only able to travel back in time, in increments of 12 hours.not forward. Once he went into the hole many many times to reach the past, he had to live through it to catch up with his future other self. The thing that is a mystery is that he had to have somehow adopted an alternate identity throughout the whole past and avoid interactions of his younger self while growing up.
shareWhich was thankfully easier to do in the '50s. And he could have moved a bit aways in the interim and then returned when the time as right. As to why be bothered I can only assume he was covering all possible bases as to how cause and effect might actually work. All though even from his singular perspective he should have be able to rule out the only two theories he'd be protecting by making sure his younger self found the hole.
When I have nothing to say, my lips are sealed. Say something once, why say it again?