I found a much better solution to the problem. Instead of forcing the character to lay down,i just remove the velocity and tada, even better than the old version and i added a missing animation name.
Video demonstration: https://youtu.be/0DGiLA8gCZM
####>>>> Installation
Add the code from the initplayerlocal.sqf file to the end of your initplayerlocal.sqf of your mission-file.