I believe they may have DNA and other evidence that could be beneficial with an arrest, but they do not have anyone in their sights at this time.
They may have a person(s) in their sights but ...
There was a case in Southern California where a man was convicted of burglary based solely on the fact that his DNA was found at the crime scene. He appealed the conviction. The Appeal Court was asked to weigh the question of whether DNA is such convincing evidence, that nothing else matters. The court said No.
While DNA evidence may be considered the same as a fingerprint and can link a suspect to a crime, a criminal conviction requires much more. The criminal justice system depends on irrefutable proof that the defendant was not only present when the crime was committed, but also that he or she in fact committed the crime.
If LE had the murder weapon (and I don't believe they do), DNA can link it directly to the crime. If semen was found, that too can be a direct link. However, if they only have fingerprints, the prosecution must be able to prove that the fingerprints were impressed at the time and not at some earlier date.
In the case of sexual assault, it should be remembered that this can also happen with an object, in which case semen won’t be found, but it's possible that fingerprints could be found on the object. That type of SA is all about power, not sexual gratification. In this case, that sort of crime scene could explain the horror LE felt when the bodies were discovered.
Sgt Holeman said, “At every crime scene, you are going to have DNA. We are still working on identifying all of the DNA that we have there”. It may be from multiple people, and it may all be from family members or friends (Kelsi had friends over the night before). Becky said family and friends had all provided DNA swabs.
Apart from DNA, IMO the missing piece of the puzzle is that they can’t place any known person at the crime scene and that’s why they’re desperately hoping for someone to come forward.
The highest standard of proof is required for criminal convictions, especially in murder cases where the death penalty or a life sentence may be imposed.
Leazenby said, “This one’s just – it’s got a whole new, it’s got a whole twist to it that even I as a 30-year veteran have never seen”.
DC said the girls were "brutally murdered" and described what happened as the "epitome of evil". "Those two girls, once we tell you all we know about them you might understand a little bit more about why it’s so emotional".
I don't think an arrest is imminent at all.