Wait...the caucus begins at 10 AM on Saturday. Now barring a Nevada-esque catastrophe, shouldn't results start to come in at about 4 PM (Eastern)? I guess they can't monitor results from the state though since they wouldn't be back east in time.
In 2008, there weren't really a significant number of result out until after 10pm Eastern:
https://uselectionatlas.org/FORUM/index.php?topic=70146.60Though, via some googling, it looks like 2008's caucuses began at 1pm Pacific / 4pm Eastern:
http://hope-for-pandora.blogspot.com.au/2008/01/washington-precinct-caucuses-2008.htmlwhereas this time it's 10am Pacific / 1pm Eastern. Either way, given the general fiasco that was the Washington Republican caucuses last time around, I would not necessarily expect the networks to be able to call the race by the time this Huckabee event starts at 8pm.