What's the 2012 case?
<respectfully snipped>
That would be the abduction on July 13, 2012 of the Evansdale cousins 60 miles North of Brooklyn. In that case, the girls were found in a park popular for fishing and hunting 20 miles North of Evansdale. It's not out of the realm of possibilities that the person responsible for their murders lives South of Evansdale and left the bodies North to throw police off. I also find the dates interesting. In 2012, July 13 was a Friday, and in 2018 July 13 was a Friday. It's quite possible that this is the same person but things didn't work out on July 13, 2018 so he kept looking for a victim (crime of opportunity) and found one on July 18.
Sure, this might be all coincidental, but there might also be a pattern to this - a sort of reliving the memory on the anniversary.