And had a proper license for it until recent changes to regulations around it's enclosure. This isn't just some guy that did it on a whim, he put time, effort, and money to do it legally for so long.
I'm not so sure. I think alligators need UVB for their spines, and there was no mention in the article (aside from a mention that the vet found spinal malformations). That and the lack of bones/organ meat was a red flag for me.
They can survive a long time with improper care. Snake Discovery's alligator previously lived in a wooden box too small to turn around in for 27 years.
ETA: he does obviously love the animal though. I would hope he had first been given education on anything that he was doing incorrectly before they took away his pet. And of course letting people swim with the alligator is probably not ideal, no matter how much he might trust it, it's still technically a wild animal.