Looking at that video, Gillon not JB called for the Roberson screen. To be honest if I had been Gillon, I would have passed to Roberson who was running free unguarded across the lane and hope that Roberson has the basketball IQ to realize that Lammers had to make a decision whether to guard Lydon or Roberson since it was now 2 on 1. If Roberson squares up and faces Lammers , Lammers would probably take a step towards him leaving Lydon alone for a dunk. It shows me that either Gillon is lacking basic PG vision/mindset or his teammates don't trust Roberson offensively. Look at the video and stop it at 3 seconds in.
First of all, imagine the reaction on this board if Gillon passed to Roberson and he bobbled it/turned it over/missed a shot. He's a black hole on offense, which is fine, I'm not trying to knock him for that in particular... But there's no way the play needs to run through him there.
Secondly, take another look at the video. Gillon either has to pass over or around his defender. If he floats it, they have time to shift and it will no longer be a 2-on-1 down low. If he takes a dribble to the left to wrap a pass around, the player out top is likely to step over and he has to thread it through. If he takes a dribble to the right to pass he has minimal room and may get trapped.
The play as-is was the right concept. You have Roberson on the floor, use him for a screen. Gillon should have waited a split second longer to allow more time to set it, and Roberson could have set it slightly cleaner, and the refs could have swallowed the whistle. If any one of those things happens, Gillon is driving at the free throw line with four options: White on the left wing, Battle in the left corner, Lydon down low, or his own shot... Plus he has 15 seconds on the clock and can pull it out if he needs to. Probing to the free throw line with the three guys you'd prefer to take the shot (in whatever order) getting set up was a fine play there... Unfortunately, two people made very small mistakes (Gillon and Roberson) and one made a still relatively small mistake (the ref).
If that call is made on the first possession of the game, it's questionable, not the worst call ever.