I am Gillian Mary Hewitt, born Gillian Mary Soady. I can't help directly with your search for Cyrille Owen, but I do know that there are still many members of the Soady family in Looe.
I didnt know my father after I was four years old and have since discovered an entire Cornish family which I didn't know existed. I have got a family tree of the Soady family in Looe descending from James Soady and Mona Clements. I could send you a photocopy of this if you like. I might also be able to contact some people to help your seach. I will speak to my cousin, also a Soady, living near Looe and see if she knows any good contacts.
Good luck
Jillie.