Kinda contradictory info here, IMO. ( Not you, pirate, the news releases!) A memorial service is usually held after a funeral for those who could not attend.....or in cases where there can be no funeral because there is no body.
Honestly, I don't have a problem with the family getting together for a small memorial service; George and Cindy obviously still believe Casey is innocent, and believing that it must be unconscionable for them to contemplate Casey missing the funeral rites for her daughter. And MAYBE Casey will break down and admit the truth if she is faced with the reality of what she has done.