You are quite welcome.

But actually, Stefan Kosmyryk is not listed as having died. He is listed as having been wounded (verwundet). The record also tells you when and where he was born. He was born in 1889 in the town of Pniow, in the Nadworno (Nadworna?) district of Galicia. Stefan was serving in infantry regiment 15 in the 12th company. He was wounded in 1915.

Unfortunately, I am unaware of any additional records that would cover his military service. Do you know where your grandfather lived in Galicia?
CK