I would let him skip. CRT is very overpriced, and so if he feels that way, he just might feel like he was forced, and in turn, make the experience less enjoyable.
I would try and see if he can get a photo with Cinderella in the lobby - I can't imagine why they wouldn't let you do that.
I know this experience is important to you, but we've done it 2x now, and we honestly don't feel that eating in the castle is beyond anything else. If he doesn't want to join you, you are able to respect his decision (saving the money is a good one), then just get some photos downstairs.
I hope you are able to work out a solution that is positive for all, Tiger