The difficulty you have experienced is the variant transliterational (sounds-like) spellings of your surname. The actual original surname was Kowerdowicz. Jan (John) Kowerdawicz/Kowerdowicz dob 1896, mother's name was Evdokia, emigrated in 1912 w/Hryhorij (probably a brother, who later may have become Harry) from Sniatyn (today Ivano-Frankivska region > Ukraine) and died in Cambridge in 1919. He had married a Catherine (Kateryna) in 1916. Make sure to search all records using all variant spellings (Kowardowicz-Kowerdowicz).
http://search.ancestry.ca/

Death Records shows John Kowerdowica.

Sniatyn church registers have been filmed by LDS.