It would make little sense, there is no way Barriss could master dual wielding in short time and Force Choke people from so far.
who says she was far? she was close enough to be very near, not only to drop the security key, and to kill those clones.
Also mastered force choke or dual blade? what that means? if she turned to the dark side she could very well be proficient enough to do it. Mastered isnt even required. Ahsoka swicthed fighting style arround the same time frame even.
As far we know barris was the only one knowing where Ashoka was ( at the wharehouse), besides ventress, but for obvious reasons ventress is ruled out. And the fact that the comunication was secured ( ashoka hacking the comunication line to make it so)
If it isnt Barris it could be someone working with her. someone we dont know, wich means they will be intruducing a new character wich i very rather doubt at this point.
All im saying cleary from wacthing this last episodes everything points to her. Remember that the girl who was forced choked said it was working with a jedi. that narrows even more the suspect list.