If there was catfishing collusion ....
I think several things were occurring in stereo, leading up to the horrific events of that day.
Keep in mind that IMO and at most, I think Libby thought she had a vetted crush, older and remote. I think she may have encountered EmilyAnn and was sympathetic to the girl she believed her to be. Probably wanted to help her. In fact, if Libby expected to meet anyone that day, I think she might've thought she was meeting EmilyAnn. (And maybe she did. Only it wasn't EmilyAnn, it was the person using that account. I can't help but to wonder if an ugly two-way blackmail didn't develop between the user of A_S and the user of EmilyAnn. Extortionist, financier, tables turning.)
So.... Libby may have been looking for a time and place to meet Emily Ann, to offer friendship and support....
Meanwhile, a darker plan is being finalized. Get Libby a new phone. Walk her through the factory reset. History *poof*. No worries, new phone is only for a week and what history it is, it'll go *poof* too. The whole phone, in fact, will go *poof* and no one will be any the wiser because no one besides maybe Abby knew about it.... and she'd be going *poof* too.
There were many phones in circulation, I do believe. Key players each had at least two. I think KAK may have made a fatal error in using the secret phone to communicate with Libby at some point, so LE had a known point of contact between KAK and Libby but no Kline phone to go with it. IMO he was forced to produce the second phone, mysteriously appearing in the kitchen, conspicuously wiped.
That error may have been the beginning of the big, long, ugly unravel....
Because IMO the strategy was to use untraceable phones to triangulate communication that day. Two parties in the know, one (the minor), duped.
IMO BG was banking on his reputation. Just a guy at the park. With his nice tidy phone, nothing questionable on it. Second phone connected to KAK, CSAM, and Libby, via her second phone. And KAK, who messed up and crossed phones.
Otherwise, by 7 pm that night, I suspect there was a master strategy to destroy the three secret phones, silencing that conversation for all eternity.
Except for the cell dump. I wonder if two numbers didn't pop up, corresponding to no one. That may well be how RA got overlooked -- his personal phone number checked off. He wasn't "the guy" with the unknown phone number... it's just he had two.
I will not be shocked to learn at trial that those two unmatched phone numbers showed communication... exactly in the minutes before and after the commission of this set of crimes.
I still think it's possible too, that murder at the bridge was not in the plan. A controlled abduction, followed by captivity, SA, CSAM and ultimately death. KAK may have been blackmailing and pitting multiple players against one another.
If RA participated in the abduction piece under threat of being exposed, and the abduction went sideways, how far would he go to keep his reputation safe? Did he wind up killing them to protect himself from discovery?
And that's why KAK knew he was f'ed. The girls were supposed to be disappeared without a trace. Girls gone. Extra phones gone. Just one guy at the park who never saw them.... walks back to his car. No blood, no mud. Extrortion against him, settled.
But the girls fought back.
Coward killed them so he'd never be found out. It almost worked.
JMO