Okay, but if we sink time, effort, and resources (those servers tend to have difficulty sometimes with RAM utilization when the first start) and noone plays it (like how SG, Splatter, and Partygames are) our devs may feel a bit less motivated. That being said...
Is the only reason I'm not completely downing the idea. We do need to look out for developer morale though. Since it is one of those games that really doesn't need others to be played there is bound to be someone who plays it, just like elite survival. There is usually at least one person there.
This is more of an issue that may need to be explored. If we throw modes at a wall until we see what sticks, we may run into issues with morale of the devs and potential monetary issues.
However there are some further things I would like to address
Prison servers are short of content. We need some way to spice it up, make it so people can't complete it in a week, some reason to drive them to keep playing even if they hit end game. I recommend rentable cells at large scale (of increasing sizes.) Maybe some areas to explore, story content? maybe. I dunno
Thematically we should try to keep up with the style of something in PZ. No idea what. I dunno where I'm really going with this line. Maybe it can be harvested to make something better.
Have a look at the main post as I've been backing up more and more ideas there of how to make it our own prison rather than a copy of someone else's. It seems new party games like you mentioned aren't sticking for the server at the moment however prison is a full game mode. A suggestion could be that once you are freed from the prison you can enter a survival world maybe and try to live there or there will possibly be an option to restart or something I'm not too sure. Open to suggestions.