Don't mislead the poor guy

As a matter of fact and law, it is not true that if the victim does not testify, the DA cannot prosecute the defendant or the court cannot find him guilty. Even if a victim refuses to testify at trial, the cop who made the arrest would, the 911 record would be introduced as evidence, and what you stated after the cop gave you Miranda warning would also be introduced. In addition, if a victim is the material witness, without her testimoney DA cannot make the case, DA could compel her to testify by subpena. If the victim's testimony is significantly different from her prior statement, DA may also charge her with perjury.