No. A voluntary program would be strictly opt-in. In Perry's scheme it automatically assumed that the parents will comply. It is the burden of the parent to REQUEST PERMISSION from the state to be labelled a "conscientious objector" to the pill. In order to do that you have to fill out a legal affadavit.
I agree it's lame what he's setup but you can't claim that it isn't 100% voluntary.
Even if you have to fill out an affadavit you can.. and if you can list religious or other reasons then they can't deny you.
Therefore you can't get out of it with 100% certainty.