I'll go for 3.
Trap being peeved with Robbie after the last game doesn't auger well. If Robbie isn't fit, and it's at most 50/50 at this stage, will Trap trust him to be honest?
Same with Longy - it would be a risk to start either if they've only recuperated in the days leading up to the match.
Having Best on the bench is a no-brainer to me. Wouldn't surprise me to see Walters and Cox start with Best and Keogh on the bench.