Good on you to go brother... You support him, that is the message you are sending.
Now you need to move back closer to your son or your chance of loosing him is very great. I lived several states away from my children because of work for two years when my two children were that age. That is when I made the decision my job is not worth losing my kids. If he is giving a talk already, without your positive influence he will be baptised shortly after and that is where the difficulties will start.
It may be difficult to get back but your son absolutely NEEDS you close to provide a normal life for him.
pbrow