Do I have to disclose a dimissed charge of battery to a CA governing licensure board?

I was charged with battery. The result of my case was a plea in which I received pretrial diversion. I have completed my pretrial diversion and my case has been dismissed. However, due to the nature of the Radiology (Health Care) program that I am currently enrolled in San Francisco I will be required to apply for a State Licensure in order to work. I recently reviewed the ARRT's (which is the governing board of the State Licensure for Radiologist) code ethics, which requires a background check. This background check requires that I divulge all criminal proceedings, namely battery, that have not been expunged. The background check also requires that I report any misdemeanor charges including charges resulting in plea of pre-trial diversion activity. In addition, I read in the ethics section of the ARRT rules and regulations that they consider pre-trial diversion activity a conviction. I discussed this with my criminal lawyer and they said that I do not need to to disclose my arrest or my pre-trial diversion to a state licensure even if they do ask for disclosure of all pre-trial diversion activity. He derived this answer from Penal Code § 1001.9. Successful completion of program; record; disclosure of arrest. However, he said to ask an employment lawyer to confirm this. I want to do the right thing and don't want to risk my future not disclosing information to governing board of my state licensure. Do I have to disclose a dismissed charge of battery to a CA governing licensure board? And if I do what is the best way to do it?