It would seem that Sir Charles Portland doesn't know where ZM73 is. He doesn't know if ZM73 is able to get in touch with his daughter, because he hadn't sent him on a mission. If we are to believe Sir Charles, that he doesn't know where ZM73 is, he surely must know someone who does. Someone in MI5, MI6, or other Government Civil service department. And yet there is a great deal of jealousy between departments, and it was notorious that one department wouldn't tell anyone else what it was up to, and so would jealously guard its various projects. If another department had found out about The Village, it may very well have moved in and taken the project over, move in and never leave, or had it cancelled altogether! So its no wonder that Sir Charles Portland didn't know about The Village. No-one would tell him! ZM73 may have worked for Sir Charles' department, but Sir Charles didn't recognise the Colonel when he came to call. Which indicates the Colonel worked for another government department, and was like his predecessors, seconded to The Village, which ultimately cost him his life.
As for Sir Charles Portland, perhaps after the episode of 'Do Not Forsake Me Oh My Darling,' he was told what had happened to ZM73 since the time of his disappearance, by his daughter Janet. Always assuming of course that after that romantic scene, her fiance explained everything to her.
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