Gomer and the Queen of Burlesque - S4-E21
Factual error: Gomer is a Private First Class and has one stripe. In his utility uniform Gomer doesn't have metal rank insignia on his collar. All Marines wear their rank on their utility uniforms. (00:06:00)
Answer: There's no indication they were meeting for the first time, in fact they seem to know each other as Sgt. Carter addresses Andy only as "Sheriff". Gomer Pyle just says his two favorite people are "meeting face to face", and obviously in the pilot episode Sgt. Carter wasn't one of Pyle's favorite people yet.
Bishop73