They're different - really?
Or were you thinking of the setup in "Let That Be Your Last Battlefield"? There's all sort of wierd stuff happening there - what's up with the funny angle the wall is on?
There's also a lot more "tech stuff" in the foyer area, compared to to the clean look of "Journey to Babel".
So this could very well be another area of the ship, as you suggested. However, the doors in JTB and TIS are (I believe) the same area.