An illustration was once used in the WT to describe how best to help worldy people come into the organization. Can't remember it fully, but it was along the lines of .... 'if someone was in a dirty puddle would you step into the puddle in order to help them out?' The point of this was that you wouldn't become part of the world to get them out of it, because you would end up getting 'dirty' yourself.
Personally this is how I feel about the org. now, I couldn't put myself back into that environment knowing that they are knee deep in ' dirty' water. I would feel that I really was a dog returning to its vomit.
But if you feel you are able to do it for the greater good then good on you for trying. I have a friend who was DF a year ago for 'normal' reasons, but because he at one time a few years back was lightly questioning some things , the elders are now very reluctant to allow him back in. He has put in a letter and had several quick chats and phone calls to the elders enquiring about when he can be re=instated. He is at every meeting , arrives after the song and leaves straight after the prayer. He doesn't even make eye contact with anyone because he was told this could be construed as him having a bad attitude. His reason for wanting back in is the same as yourself, it's to try and get people out. There is nothing more he can do......he is so frustrated at how difficult it is to get back in yet he is still determined to do it, while the elders seem just as determined to keep him out, with no real reason.
All the best to you !