IMOO, I think the reporting that the DNA couldn't be uploaded into CODIS is a way to make the perp feel relaxed and like he is getting away with this and to NOT RUN, in order to let IGG have a crack at it. IGG needs time--I think it was a smart play by LE to buy time to let IGG do their thing.
I think (or at least I hope) they have a really good feeling about who did this now and that is why they are allowing the family into the home at the moment.
Crossing my fingers, something breaking will be announced soon. Praying for NG's family.