Possible meanings are 1) "his" and "him" refer to the person who has died, or 2) only "burns him" refers to the person who has died, and "his relative" could be translated as "a relative."
# the one who burns
This phrase translates a word that refers to a person whose duty is to burn the bodies of family members who have died and for some reason cannot be buried.
# in the inner room
You may need to make specific that the house had one or more inner or back rooms in which people could hide from those in the outer or front room where the dead body was lying.