Tazendra has been rather interested in the barrier, so she could work as a distraction or help magically penetrate the barrier. Since in canon, she broke through a defense powered by a powerful being* by channeling power at it until it broke, she might, mods willing, be able to break through. On the other hand:

1. It will be noticed.
2. It could open her up to Malicant's influence. Or just being stabbed in the back or captured for interrogation purposes.

Hopefully, her being a nuisance can further others' more subtle attempts. You probably wouldn't even have to tell her your plans.

* As in, 'The beings who the Dragaeran gods used to serve before they rebelled'.