No stipulation of facts between the parties or their authorized representatives shall be admitted into evidence unless it has been reduced to writing and signed by the parties or their authorized representatives or, upon leave of the presiding officer, dictated into the record during a prehearing conference or hearing at which all parties to the agreement are present, have waived the right to be present, or have received reasonable notice that the settlement will be read into the record at that prehearing conference or hearing.
16 Tex. Admin. Code § 22.228