I'm stuck in the luxury suites of the casino, there is a service door that won't open and I can't go back....anyone have a clue ? I used every terminal I found, opened every door...

I just figured it out... There are two suits on the south west side of the map, both have a Scarlett hologram roaming. Make your way through the busted walls into the south room and on your left will be a door. Go out that door into the hallway, to know you are in the correct hallway there will be one of those dispenser things on the right. Take a left at the first hallway intersection that will take you to the kitchen where you can fix the gas leak. Doing that should give you access to where Christine is.

I can't understand why I didn't saw this room before. I turned and turned for a very loooong time.
big thanks.