That isn't what I heard him say. I heard him say that the condition of the remains when it was found was consistant with a body that was dead 4 to 6 weeks. That is not the same as 'died in middle of January".
Check out my reply in #928m of this thread. Then tell me the difference in meaning.
Today's witness gave his opinion of the range of time that he believes the body could have been dead for. That isn't the same as giving a time of death. They are close but not the same. <P