See Union-Castle Chronicle pages 225 to 228,

The loss of the "Walmer Castle" and chief officer Mr. A. Lawson, the senior surviving officer's report.

Mr Lawson Chief Mate took command with the death of Captain Clarke on the third attack by enemy aircraft.  By this time the "Walmer Castle" was largely a burning wreck and Mr. Lawson's chief task was to evacuate the survivors of the "Empire Moat", "Baltallinn" and the "Walmer Castle" crew.   It was largely due to his efficient organisation under extreme circumstances that so many were saved.  

For this he was awarded the M.B.E. and received Lloyd's War Medal for Bravery at Sea.