No you can just wait at the top of the crane until the gas overuns and kills you , all the battle pass XP is time based so it does not matter if you make it out alive or not and its the exact same amount of XP you would get for running around killing Zombies and bosses
I have seen videos of people trying to squeeze the most out of the time in game and the only other suggestion was to go to the story missions (end of act1) before the end of the gas comes in and wait on that map for the counter (adds another 30 minutes) , but its just as easy to redeploy and go back up a crane.