Will it be safe for the police to send the dismissal materials to the police station through lawyers?

Yes According to the provisions of the Lawyers Law of People's Republic of China (PRC), lawyers can represent their clients in legal aid activities, including applying for dismissal of improper criminal cases. If a party needs to dismiss a case, a lawyer may submit materials to the public security organ on behalf of the party and request the public security organ to handle it according to law.