Oh so they're already arranged it? Have they arranged for ds to physically go to a contact centre? I don't quite understand.
I read as if they were just making noise but hadn't actually done anything.
2 options then- bribe ds to go and join the call. He can then choose to sit and say nothing, explain why he thinks it's weird then end the call, or maybe it won't be as weird as it sounds.
Or write again repeating that ds will not join a call with a 3rd party but is willing to video or phone chat directly at xyz times.
I honestly don't think a court would make him do it if he doesn't want to. They can't force him to speak anyway, even if they somehow physically force him into the building, so I just don't see that they would make any sort of order to that end.
Something to think about- if this is a properly arranged thing I guess ds would get to speak to the person first before a 3 way thing with his dad. If he felt able to tell that person how he feels then they could relate that to dad? He might take it better from a 3rd party.
That's me assuming it's a bit like a family mediation thing where the mediator will speak to both people separately.
What do you think about asking for details of the person and contacting them in advance?
Sorry this is all falling on you. It's completely unnecessary. And I can totally see my teenagers also just digging their heels in when it gets this stupid and refusing to have anything to do with it.