I honestly don't know how this happened. I was unable to reproduce it, but it randomly happened to me the other night as well.

I recently encountered the same problem. I have a feeling that it occurs when you touch doors that are not related to the seat where the player is sitting.
This is an assumption, I was not able to repeat it 100%

Also it can't be fixed through GM, people fully stuck in compartments.

Happens all the time, on vanilla too. People get stuck in vehicles, they cant exit, GM cant help them, reconect (without player deletion) didnt help eather. Not very nice for gamemodes where your game life matter.

A video about how you can repeat the bug with 100% probability
(The explosion at the end was caused by the gamemaster, because he could not pull out the remaining passengers, the only way is to kill them.)

https://www.youtube.com/watch?v=4ItupJyx5y4

In T167204#2635971, @reygasai wrote:

A video about how you can repeat the bug with 100% probability
(The explosion at the end was caused by the gamemaster, because he could not pull out the remaining passengers, the only way is to kill them.)

https://www.youtube.com/watch?v=4ItupJyx5y4

Thank you, can you also provide the version number, whether the server is modded (and if so, which mods does it run?)

In T167204#2636093, @Geez wrote:

Thank you, can you also provide the version number, whether the server is modded (and if so, which mods does it run?)

Game version: 1.2.0.76, no mods
Testing took place on a dedicated server