I had three sugar gliders. Jack, Rose, and Bell. Jack mated with both. Bell had Ty who passed away at 6 months (22 days ago) and Rose has had Finn (1 year old), Kiwi, Aang, (6 months old)Tiny, and Quinn (21 days old). I have taken care of many joeys, but I have never had this problem before.

When ever I take out Tiny and Quinn they are cold to the touch. They are cuddling with Kiwi, Aang, and Rose, but they are still cold. I warm them up and then give them back. And when check on them later they're cold. Why?

Possibly Torpor but unless the room temp dropped it's unlikely. I know we just got out of a 5 day -42°C coldsnap but we had the heat cranked up to 73°F so all was good.
Sorry hope everything is okay with your youngsters.