M F Davidson was probably Michie Forbes Davidson, brother of the Gordon Forbes Davidson who had been godparent to Sara Sophia's younger brother Thomas Waterman Whittle Jr.
August Behn was almost certainly (Theodor) August Behn§, the business partner of Valentin Lorenz Meyer. In 1840 these enterprising merchants, originally from Hamburg, inaugurated Behn, Meyer & Co Ltd, which became a mighty trading company in the Far East, existing to this day.
§ The Straits Times, 9 Aug 1936, p15; eresources.nlb.gov.sg/newspapers/Digitised/Article/straitstimes19360809-1.2.114.aspx