Actually scratch the instant die part, I believe it was for certain spots on map where tank would spawn but just be unable to get out, like the off-the-map section around the Dark Carnival coaster "tunnel".

Patch a number of years ago made it so if a tank spawns in certain glitched spots where it would just instantly die, they move it to another spot and spawn it in after the players have moved through the area. Decent compromise, less stuck tanks and no teleporting the tank to a spawn right in front of the survivors with no warning. You only really see it happen on a few maps though, and there are still spots where tank just dies anyhow.

you didn't know this stuff has been happening for like forever now? happens very often on dark carny coaster too.