The tl;dr
The mystery surrounding the murders of Libby German and Abby Williams remains unsolved.
On February 14, 2017, the bodies of Abigail "Abby" Williams and Liberty "Libby" German were discovered off a hiking trail in Delphi, Indiana. The young girls had disappeared from the same trail the previous day. Libby managed to record video of the suspect who's come to be known as Bridge Guy or BG for short.
Two years later, on April 22, 2019, Indiana State Police held a press conference in which they released new audio, a short video, as well as a new sketch of the suspect, made at the same time as the first sketch. (see below). This sketch is now considered the primary Person of Interest (POI) in this case. It's not currently known whether or not police possess DNA from the suspect or what was the cause of death.
Police insist the case is not a cold case. But three years later, no arrest has been made in the slayings —and police have remained mostly tight-lipped about the case.