As I said, in a private world, the world is managed by the world owner. When you decide to join a private world, you have to realise that the world is being managed by that person. However, if that person decides to stop managing the world (because they stop playing the game or because of any other reason), you will no longer have anyone in control of the world.
This is a risk that you have to take if you want to play in a private world. For this reason, I would recommend you do not join a private world unless you know the world owner. You should consider joining a public world - where there is more activity, and things are monitored by the AM staff.
In short, there is little you can do except put up with it or join another world.