There are other royal mummies that have been identified by cartouches from around that time. The DNA problem begins when you read the history. The Egyptian pharoahs practiced inter-family breeding on a grand scale. Contructing an historical family tree for any Egyptian dynasty is worth a migraine headache. How they can tell the right mummy from the wrong mummy for DNA testing will be fascinating.
There was also a theory that young Pharaos-to-be may not have been the products of the married brothers and sisters' unions...it's still gonna be tough.