I believe that the VI used the word 'around', which to me means approximately. my timeline is approximate, I said that, along with the word 'speculation'. I also invited others to amend it. Would be interested to see your timeline?
Well, I am not convinced she even went to the desert that day, quite frankly. Perhaps wherever the parking lot/360 took place, where BT is said to have taken a photo that day, wherever that is, is where she 'disappeared' from.
But here is a stab at it:
Left home at 8:15 - witness/video
Gas station 9am - witness/video
something about a 360 photo she took that day (haven't seen it, can't prove who exactly took the photo), with a parking lot nearby
arrive at rock formation say 10:30am
hide the key under a rock (that makes sense, seeing they were just going for a walk to see a rock formation on their way to their camping destination)
walk for a mile and back again (how long is the estimated time for a couple of fit older people to walk that far again?), RT takes some photos, he's packing up, and she disappears into thin air.. maybe an hour later.. 11:30am
He goes back to the RV, she's not there, calls her name, waves his arms, starts to get worried around noon, as relayed to B's family
-the rest is pure speculation by anyone, which may or may not end up being against TOS, but there is a big blank spot between 11:30am-12noon as speculated above, and 3:30pm when we know he made the phonecall reporting her disappearance. He says he searched for an hour.. but that timespan is 3.5-4 hours, not one hour.
We don't know if he had to drive the RV somewhere else to get enough phone reception to make that call. And if he did, then I guess that would provide a good explanation for perhaps why the truck may have been unhitched and rehitched, or why tire markings might show arrival, departure, arrival, (if they did show that).
We don't know much of anything.