Yeah it would be great.. but sorry this will not happen with the current holder of the data.
I accept what you're saying and why you're saying it, but honestly It's hard to predict.
It could easily be that between him and the manufacturer they screwed up the ground plane and the guy is too proud to accept it. That doesn't mean that he won't privately have taken you seriously. Or even if he didn't, then he'll figure it out soon enough when someone else tells him the same thing.
It's only a real problem if they don't have the ground plane layout at all.
Of course, people should be wary of putting money into any scheme like this. It's still too early.