OK I did a lot of debugging and I figured out what the cause of this mess is. But unfortunately I do not know a permanent solution.
The thing is that all characters in game are represented by so-called state machines, and there is a list of all state machines. M_maria is the name of the state machine for maria, and machines['maria'] is supposed to be the same in said list. Similarly, the same is valid for machines['tina'] and M_tina.
Somehow, in your game, the instances of machines['maria'] and M_maria are different -- they are supposed to be identical but are not. This means that whatever the game does to machines['maria'] does not affect M_maria and the other way round, leading to your problem.
If you open the console in your game *before* you deliver the pizza to Tina and type
Code:
machines['maria'] = M_maria
the game will progress normally and you can meet Maria in the storage room later.
However, as I said, this is not permanent and will not survive saving/loading the game, and you would have to apply that command every time you load an affected save. I could not reproduce how this happened to your game.
Maybe you can figure out the save in the past where this issue happened first. If you load a game and in the console you type
Code:
machines['maria'] is M_maria
(note the "is" instead of the "=") and get the result True, everything is fine. If you get False, the bug already happened.
I might include a fix for this issue in my mod (see signature) but I am uncertain if it will be of much use because it is, as mentioned, not a permanent fix and would only be fixed while using the mod.
You might want to file a bug report on kompas web site for this...