Otto Hess served in 3 troop, also known as 'X' troop, of the inter allied commando under the alias of Peter Giles.
Whilst the circumstances of his death are not known to this Archive, the following is recorded on the Special Forces ROH website:
"3 Auxiliary Military Pioneer Corps (AMPC) Training Unit
165 Company,Pioneer Corps
10 Commando (3 Troop) 1942 (left due ill health)
General Service Corps (Lt) 1944
detached to work with Yugoslav partisans 1943 (SOE)
award King's Commendation for Brave Conduct *
POW - executed Yugoslavia."
* Source: London Gazettes Supp. 37595, page 2742 - War Office, 6th June, 1946 posthumously granted King's Commendation for brave conduct.