I finally found it, called mountain dance.

And this is where Jesco White is teaching the girls how to dance.

I still haven't figured out this function - there are so many parameters, again poorly documented.

@bmSgtav The only two things I can share with you is that for addons specifically, every once in awhile the spawn name and the folder name are different. This is dumb, but that's the way the author did it. Why keep it simple and consistent with 99.99% of other addons, right? So in that case, you go back to the instructions to see what the spawn name is. Interestingly, many addons don't even have instructions which makes sense since it is a no-brainer installation.

The second issue I found is that some just won't spawn for reasons unknown. You can get a feel for that in the comments section of the mod, i.e. if you see lots of comments saying couldn't spawn you might be one of the unlucky ones for whom, reasons unknown, it just won't work with your configuration. For example I can't spawn the Porsche 935 which the author has as porshe, regardless of how i spell Porsche.

@V3ry_H1GH Good!

https://www.gta5-mods.com/scripts/travel-to-north-yankton

@CodeMunk What I don't understand is how you will use this. More importantly you will need to look at some tutorials on how to script for GTA V even if you are experienced with C#. You will need to learn how to spawn vehicles and peds and then you can write whatever logic you want to add to that. Again, I really don't understand why you would want to know if a ped is in a given vehicle when there are hundreds of possibilities - i.e. the probability is near nill. Also, your example refers to the player - and as the player you know exactly what vehicle you are in - unless you teleport randomly into a vehicle for example. You're French I assume?

@Chocolate-Egg And your friends have only 1 version of Menyoo, for both SP and FiveM?
Not sure if this is what you're experiencing, but worth a look:
https://github.com/MAFINS/MenyooSP/issues/85