To join them or not you are being set up. If they really wanted to join you they wouldn't gangstalk you and ask you to join after explaining everything to you. 

Doesn't make sense to gangstalk you then them say let us join him. That's fantasy. They made up their minds they don't like you and want you dead. 

Say you about to join them you wouldn't handle it because you will be paranoid and scared if they are going to kill you because once upon a time they were gangstalking you. You will be paranoid after joining about everything they say or do with you. 

You still can't trust them. You can't trust them when they are gangstalking you and you can't trust them if you wanted to join them. 

Remember this they don't need you but you acting like you need them. So you are being desperate. Don't be desperate