purple my gut instinct would be to get it in writing to protect yourself, like you say. In a way it does mean you're not disengaging, but I find that when I'm doing the same thing it doesn't affect me in the same way as when trying to reason with them with hope. As long as you know you're doing it to state your case rather than with any expectation that they'll see sense, it's bearable.
Do the sols work Saturday, could you run it past them this morning? Failing that maybe a helpline, WA or similar, if it would help you feel sure that it's the right thing. I think generally advice is to document everything though, and email is the only way I can think of that you can do that in this case.
2012 I'd say the same thing to you I think, I completely understand where you're coming from and have been there too. That young I don't think they do have a legal say so other than forcing them to go, as the RPs it has to be us saying no to contact. But, contact has to be in the best interests of the child and it's your judgement call on whether forcing him to go is. I'd document everything you can, whatever you decide to do, just in case you need it later.