The previews tend to favor safe teams, but I believe it has happened where a team was shown struggling on a task and were eliminated that episode. I think it was Margie/Luke from Unfinished Business season (18) during the tea-tasting challenge...?
But with so few teams, how do you "favor" one when all are shown at one point in the preview?
On the order of finish note, Justin says "we are so screwed" suggesting a penalty (at their check-in, whatever order that may be...) If they checked in first or second, I don't think "screwed" would be the first word. If they checked in third, then I think it would be more "screwed" because there is the highest chance to get eliminated. Although, the editing could also pull that from somewhere else in the episode timeline...
My guess for order of finish: 1. Joey/Kelsey (seem unflustered, just a "wow") 2. Logan/Chris (more shock) 3. Justin/Diana (with penalty) 4. Cheerleaders (with penalty).