Hello..
I think once he has been out and had a taste of freedom again.. he will do anything to get out..
probably your best bet is to keep him in full stop.. It will take about a month or so for him to get used to it..
other than that, I have a cat enclosure they can go into when the weather is nice.. they wait by the door when its a nice day.. or you could have a harness ....
I have tried feliway with mine and seems to have made no difference at all...
