Agree,.... My Kodah did that and I put him by himself. He was still in the same room next to the others but out of grabbing range. I still did pouch swapping. Every morning I would take the gangs pouch out and put it in Kodahs cage and that's what he had to sleep in.
On the 5th day as I was messing in the gangs cage, Kodah hung on the side of his on high alert! He was watching every single move I made. As I was approaching his cage door with pouch in hand he jumped to the front of his cage still all alert.... I moved the pouch within his reach,...he grabbed it from between the bars and started sniffing for all he was worth. I got it away from him and opened his door,... before I could even get the pouch hung he had jumped into it. He stayed there the entire day.
I took that as a great sign and I did intros the next morning..... they have all been together since.
He just needed a time out and to remember what it was like to be alone, and he decided he didn't like it much.