Sure, I'd be glad to and I also invite others to chime in with their thoughts.
The vomit at CR/MB's apartment could be hers. She could have been taken away (not necessarily deceased) by approximately 3:30.
She could have also been taken from JR's by approximately 3:30.
JR, in his cover story, adds an hour to the timeline for Lauren to pull herself together and leave on her own.
Included in this hour is Lauren making calls which serves to attempt to prove that she was still there upright and alive.
I agree the vomit is more likely hers. As someone pointed out earlier a side effect of head trauma / concussion is vomitting. (they were talking about CR getting punched). According to PI's she hit her head at least 2 times very hard on concrete and/or pavement. This could have done more than given her a concussion, she could have had a skull fracture and possibly a brain hemorrhage. I'm sure the PI's know this... so when they graphically explained these falls, they know she could have been in need of medical attention. She very well might have died right there, or moments later in JR's apt. The Vomiting could appear to them to have just been from drinking, so calling an ambulance isn't likely. of CR MB and JR, only CR was around when her head was slamming down. He may not even have noticed that she hit her head. (since he has amnesia for real or not, if he did notice, he's forgotten)
I recall in early conversations that it was said JR was over there at CR/MB's or some other 3rd person. If it was JR, he was likely called over (by knocking on his door) to come get LS by MB. I could see if JR thought she was just messed up he would bring her over to his place. If a few minutes later she stopped breathing, perhaps he would try CPR. Perhaps someone with medical knowledge could comment on how quickly someone could die after serious head injuries while also being intoxicated (and regardless if drugs were in her system). It seems to me it could happen, shockingly fast. So fast that CPR would obviously not be having an effect. Perhaps some hesitation, thinking of culpability for the situation and then trying CPR some more... but seeing that she had no pulse, and was not breathing. It seems a decision would be made to to either call 911 or hide the body.
Now, looking at it the other way... she's out but not dead, where would you take her at 3:30? So that you could be back in under 1 hr. AND make calls to mark the fact that you were home. This would mean JR was waiting for such an opportunity and transferred her to another location or another person. In either case, that could mean she is still alive. What would be the motive for this sort of activity?
I can see JR being the party kingpin, trying to help a friend that he helped intoxicate... but it's a bit harder to see him trading her off as a commodity.
Yet clearly there are such people.
I'm more inclined to think she died and he's covering it up. It think he helped get CR and LS messed up, wasn't aware of how serious her injuries may have been (perhaps he could see she hit her head) but either way... if she winds up dying at his place, he could easily have panicked and decided to quickly move her. I'm not so sure at this point, if he moves her himself or involves someone else to help. It's such a stretch that a guy who is supposedly involved with Drugs would know someone would could help move a body (especially if he explained it as he saw it... accidental but he could be blamed for it).