Well done with the private pilots license and keep going for the CPL Marcson. I am neither a lawyer or a US citizen but I would imagine you will be fine. Many organizations do not consider a driving violation as a criminal offense (except DUIs), you are seeking it to be expunged and I might get your lawyer to check if it was even an offense as US states have to accept overseas licenses by treaty. It seems like a very minor mater and a lot of people have minor bleamishes in their lives. Don't worry and good luck!