Can the meeting be rescheduled? Because it seems like the meeting can't possibly accomplish anything until the dysgraphia question has been answered.
Any other advice I might offer would depend on the nature of the conference. If this is the standard, once-a-year, fifteen minute conference teachers are required to hold with parents, and it can't be rescheduled, then I wouldn't worry too much about it either way. It would be perfectly acceptable to politely opt out of this kind of meeting if you're already having lots of contact with the school, which you've implied is the case.
