Trying to clarify things, as I understand them, so obviously, these are my opinions/speculations based on what we know(or think we know)...
First, I believe that whether RL participated in this crime or not, in the eyes of LE, the girls simply be found on his land makes him "involved", and that alone(girls found on his private property) is likely enough PC for the SW.
Second, since we don't know where the girls were between the time they dropped off and the time they were on the bridge, I'm willing to speculate that they could have ventured onto RL's land during that time, and had some sort of interaction with him, or simply been seen by him. I still can't see RL being BG, but accept that it's possible. I believe RL is plenty agile, strong, etc to have perpetrated this crime, I just can't get to a motive.
Third, given the meticulous work and seemingly tedious attention paid to detail in the videos by GH, I came away with a few things that I feel fairly certain of: a) Liberty was ahead of Abigail on the bridge, probably throughout the whole span(?) b)in the photo of Abigail, BG is nnot on the bridge yet, and c) when Liberty reached the end, she turned to take another picture/video of her buddy, and saw BG nearly on top of her(assuming, as several have, that blur in the one photo taken from video is actually Abigail).
Now, if those facts and speculation are correct, we can assume that LE won't release any more video captures because, quite possibly, in the next few frames the crime is commencing. Maybe he is subduing Abigail, or worse? We can also speculate that shortly after, the girls are directed "down the hill", and are probably not alive much longer afterwards.
Back RL and the SW: I assume/believe that the SW would have been good procedure regardless of what LE thought of RL's alibi. Statistically(and LE operates largely on statistics), the property where murder victims are found has a high likelyhood of being the scene of the murder, and the property owner(and ALL of his property) are going to be closely scrutinized. If his lawyer advised him to be silent due to the pending probation violation, this would have been frustrating to LE, and maybe served as a catalyst for the SW, but again, I believe PC was there as soon as the girls were found.
The simplest solution is obviously that RL is either guilty or a participant, and this investigation may well come to that conclusion, however...I hope/pray/beg, that if the evidence DOESN'T bear that out, that LE not get "tunnel vision", and be become unwilling to look at the possibility of something outside their usual profiling formula, because from some of the things I read in the news, there are subcultures of the criminal underworld which seem to be evolving, and LE would do well to pay attention, if they aren't already. This case has affected me on a very personal level, for some reason, and I get on here each day hoping to see that the person(s) has been charged and is in custody. Trying hard to stay optimistic about that. If nothing else, in researching these kinds of crimes, I've had my eyes opened to how dangerous it can be to be a woman or young girl in this world we live in. That's heartbreaking. Ladies, stay safe. And my fellow gentlemen...BE gentle men.