Up to speed now....a few comments and hopefully @Runin530mtns can comment as they seem to be the "boots on ground" local (and not connected with family). I also assume @Runin530mtns lives in Prosser Lakeview Estates so it was good to know they are (finally) canvassing that area since there seems to be a couple of back roads into the estates from the Park or someone could have been in attendance/involved from there.
A. FBI is involved as noted upthread because disappearance was on National Forest Land (but also as it may involve across state lines abduction. More below)
B. I know from my summer southwest travels that almost all campgrounds in the Sierra's west range are swamped particularly on weekends. All types get out of Sacramento, Reno, etc. to beat heat or just get out in the mountains. No reason to think that MANY party attendees might have been from the surrounding campsites particularly on a Friday night.
C. Just watched interview with Jaegger (now identified ex-boyfriend). While someone upthread said he was "cleared" and is helping family search, I would be interested in the source of that comment. <modsnip: Quoted / referenced post was modsnipped>
D. Lost in @megs1477 timeline was an entry that FBI initially focused on "Site 4". One possibility is that site 4 is in the Lakeside campground. see screen print of the only "Site 4" I could find on the National Forest website of the area.
E. <modsnip: Quoted / referenced post was modsnipped> Does KR really try to go to Reno on a whim from the party or does someone she meet suggest it as Casinos are open 24/7?
F. Without further input from friends and family concerning mental state, a disappearance is the least likely, but not impossible. (The Lana Del Ray lyric line is a typical teen angst sentiment.)
From my experience over the last year in AZ missing persons, there is a lot the family (and investigators) won't be sharing about lifestyle, relationships, etc.
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