There’s a really good chance Ernest was on the Hell Ship Hofuku Maru.
The roll of honour at http://www.roll-of-honour.org.uk/Hell_Ships/Hofuku_Maru/html/l.htm lists many men from the 4th Battalion Suffolk Regiment.
Labour Force:-From Thailand/Burma Railway via Singapore
Notes:-Alias: Fuji Maru, Fuku Maru, Toyofuku Maru. Hofuku Maru was sunk 1944/09/21 by US aircraft
http://ww2talk.com/forums/topic/20064-hofuku-maru/ really interesting! War Crimes Trial relating to the Hofuku Maru