The Labor Incident Adjudication Rules Article 51

If the movant withdraws the motion for a labor mediation, the clerk shall notify the opposing party and the interested parties participating in the mediation. However, this rule does not apply if the said parties are present on the date of the mediation and are informed of said event.When a labor mediation is withdrawn, the civil action portion of the combined mediation case shall be handled in accordance with the provisions concerning a failed mediation, as stipulated in Article 19, Paragraph 3 and Paragraph 4 of this Act.
中文原文 勞動事件審理細則第51條
聲請人撤回勞動調解聲請者,書記官應通知相對人及參加調解之利害關係人。
但於調解期日到場並受告知者,不在此限。
勞動調解經撤回後,其合併調解之民事事件,依本法第十九條第三項、第四項關於調解不成立規定處理。

English translation for reference only; the Chinese text prevails. Not legal advice.