I FOUND MY NAME! Keiles!
Most likely the name was spelled Kejles as this commemorative plaque to the Jews of Siemiatycze suggests:

It reads: "Here lie the mortal remains of innocent victims murdered by Hitlerite butchers in the year 1942 in the city of Siemiatycze / of children, women, men and the old / 70 people in all / among them Efraim Kejles / Abram Ekstrak / Mejta Lew and others / Remained alive in deep sorrow and conducted the exhumation Joshua Kejles / Honored be their memory
Plenty of info about the Jews of Siemiatycze, for example photos - check Google