I know this has been discussed in the past but I would like to know the latest information on exiting the Sistine Chapel and accessing the entrance to St. Peter's without going through the entire Vatican Museum. The last time we entered the Chapel we exited into a sort of alley area where there was a WC and went around the corner to the right and the entrance to St. Peter's. I recall the door said group tours. Can it be used?
We just did a tour there last week and while yes, the sign says that exit is for tours only, there were so many people cramming through the door that I don't think it would be difficult to blend in with a tour and using that exit. And yes, it exits into an alley kind of area that is adjacent to St Peter's. Good luck!
Well, even some of the tour companies - such as the outfit linked below which is quite often recommended on the forums - state that people leaving tours early to spend more time in the museums may not be able use that door. It's up to the whim of the guards on any give day, and considered a perk of paying more for a tour so it's not 100% certain you'll be able to exit this way.
https://theromanguy.com/tours/Rome/Sistine-Chapel-Vatican-Tour
"Important! If you choose to stay in the Vatican Museums, you are welcome to leave the tour and skip St. Peter’s Basilica. However, if you choose to do this, you will lose the chance to use the special entrance and skip the lines..."