we just starting chelating recently. he is 5. we did not vaccinate him. I consider the risk for kids like him, and yours, that are very sensitive to be far to great to vaccinate. the medical system is a one size fits all. a certain percentage of people suffer immediate harm from vaccination, probably kids like ours. others suffer hidden long term damage which the system is not designed to pick up on.
of course I can't tell you what to do, but, I think that vaccinations are an extreme risk for sensitive children. We have no regrets about not vaccinating. its not a big deal at all. your child will thank you some day.