An update to the timeline from an article from KOLO TV in Reno reporting on the testimony at the preliminary hearing.
"Osborne also testified that he was at the condo when Charla Mack arrived with the couple's daughter the day of the killing and watched television with the girl upstairs while Mack said he was going to talk to Charla.
[b]Fifteen to 20 minutes later, Osborne said he heard his own dog barking and that the dog came through the garage door into the condo ahead of Mack.[b]
The dog had blood on it and Mack had "a weird look," Osborne said.
Pressed by prosecutors to explain, Osborne said the look was "scared. I don't know how to describe it." He said his dog had blood on its "face, throat and feet."
"Just from that, I freaked out. I didn't know what happened. I took Erica and the dog outside," Osborne said. He took the girl to Mack's mother and telephoned police."
Note that Dan Osborne states that it was 15 - 20 minutes after Darren went to talk to Charla, that Darren returned from the garage. Also note that he states that the dog came up the stairs ahead of Darren.
There's more details at the link below.
http://www.kolotv.com/news/headlines/3781532.html