In which case his family should be either booking him in for help or distancing from it before they get the backlash of it.
Everybody wouldn't have believed him as it sounded like nonsense from the start. If you are now saying he doesn't believe it himself and he is addicted to attention why were his family believing it and going to look at fancy houses? Doesn't add up.
If he has no "condition" as such and just did it for a bit of attention then I don't see any reason why he shouldn't end up in court because of it if he carries it on.
I think you have to timeline this a little..
So the first story is "Hey, I've won £14million gambling!"
"Sure Dale"..
"Hey, I've found a great house. Lets go and have a look round"
*sigh" "OK Dale, sure". *what's the harm in going for a look round a house*
...and then it escalates.
"I've put an offer in and it's been accepted"...
"....oh... right.."
And then you're into the situation I described above. It's go along or tear the walls of your life down.. but since being pictured looking around that house in August you'll notice there's been no reference to his wife's involvement or engagement with the story since.
You're right. Doing nothing since isn't enough. But that first house viewing isn't proof of someone purposely feeding the story.