I have this card showing the Serbian Order of the White Eagle with crossed swords ( Military Award ).
The card details as follows :-
" Instituted by King Milan Obrenovitch 1 in 1883, to commemorate the restoration of the Kingdom in the preceeding year.
The Order is divided into five classes, all of which are awarded for both civil and military services.
The Badges awarded for military services have crossed swords below the crown, and are worn by Serbians, for war services, with a scarlet watered riband.
A good many British naval and military officers received the Order, for services rendered during the Great War.
A double-headed white eagle is the ancient symbol of Serbia ".
It seems that all 5 classes had crossed swords, if they were awarded for military services. So Captain Roberts could have had the Order Class 3 with swords, due to his being a military service award.