I wonder if the club had CCTV. It was said corrie was asked to leave, he obviously wasn't with his friends at the time he was ejected so who was he with? Did he arrange as he was escorted to meet a girl he was talking with in the spot he was sitting? Makes sense that he could have been and would explain why he didn't want a lift in a car when asked, because he had plans to meet someone. I used to live in a village 8 miles from a town like BSE we used to go out in, the only way any of us would walk that far was if we have absolutely no other options.
Going back to the doorway, Alcohol increases in the blood after your last drink so at that time he sits down and after the food maybe whilst waiting for this possible person just fell asleep. Whilst asleep some chancer rummaged in his pockets and took his wallet and phone. Corries phone wasn't a valuable iPhone and probably had a password so took money and threw phone and wallet in the bin. Corrie wakes up discovers he has been robbed, sobering up, cold, and now wondering how the hell he is going to get home, on waking needs a pee.. (Makes sense, he's been drinking and had a power nap, pretty sure he'll be needing to go) - in the CCTV when he is last seen he looks like the way I explained, defeated, cold, sobering up.
From then on I have no idea like any of us but am with he either hitched a ride, got on a unlocked bike, found a hidden away area to get his head down for a couple of hours before daylight or walked back home. But I would be surprised if he did walk he would be treking off road even if there is a short cut. When any of my friends got cut short on a night out the shoelace express would be on the main a roads. It also wasn't unheard of to get into someone's car boot if offered a ride.
I think corrie succoming to one of these options is more likely. I just don't buy him catching a nap in a bin, even homeless people don't do that. And if he was forced into it he would have put up a fight and made noise. I know we can't rule out anything but I do think his fate was met but a set of unfortunate circumstances which unbeknown to him at the time would make him untraceable until his body is stumbled upon.