Questions/ poking holes in S2 Ep4

I am confused about the last scene- Irving being retired out in the woods. Are we supposed to presume his outie just woke up standing there with everyone? Wouldn't that be problematic explaining what's going on to his outie, and his outie being able to see/meet the others around him who he worked with? Or do they have some way of putting them to sleep essentially and then waking up the outie later on? And if they do, then why wouldn't Milkshake have used it to put Irving to sleep when he was drowning Helena?