Basically, she gained 1x/2x 10% TM so a total of 20% TM assuming Han crit twice. Since you stunned Thrawn, he has to take a turn before Barris which didn't happen because his Thrawn is crappy modded.
Example 1; 280 Thrawn - 150 Barris -> Thrawn will skip his turn as he's stunned and Barris won't be able to cleanse him. Speed gap here is too huge.
Example 2; 180 Thrawn - 150 Barris -> Barris will go before Thrawn as she gained 20% TM putting her ahead of Thrawn resulting in Thrawn not skipping a turn because Barris cleansed him. Speed gap between the two is too minor.