Note that a criminal case cannot be the subject of a settlement, as a rule. What is being settled is the civil aspect of the criminal case.
If the complainant and the accused/respondent agree to settle, the complainant is often asked to execute an Affidavit of Desistance. Thereafter, the criminal case will be dismissed not because of the settlement but because it will no longer be possible to prove the guilt of the accused/respondent as the complaining witness is no longer willing to testify against him.
A criminal case may prosper even without the private complainant for as long as there are independent evidence that can be used to secure the guilt of the accused. However, it has become a practice here in the Philippines for courts to dismiss criminal cases once the complainant executes an Affidavit of Desistance.