JW's can be very vindictive, petty and officious when it comes to exercising the mere bit of power they are allowed to have. They like to think they are being loyal to Jehovah but in reality, their motivation is purely personal.
We feel quite powerless when we lose someone in death and sometimes all we have left of the years we spent with them, is the mention of our name in their obituary or their eulogy. Too bad they're using this one last opportunity to show Christian kindness to her non-JW family, to be so small minded.
Go to the funeral and show them how decent people behave in times like this.