Asked jsoledout(or something like that) on XBL. You get hit by Vajra, and then she dashes over to you(and she can get to you in the blink of an eye) and just Feral Crouches. If you neutral tech, SOMERSAULT! into free pressure. If you back tech, she teleports forward and mixes you up. If you forward tech, she teleports back and mixes you up.
Considering how her mixups work, it's very ambiguous and very easy to get hit. It's definitely not the same as getting a combo, but a Vajra hit does get her in and that's where she wants to be. Since tridash characters have an easy time escaping from her by being in the air, it's definitely the assist to use if you want a chance to catch them. It's less useful against some characters, though.