http://tbm.eqresource.com/pohealtharmoraugvendor.php Is there a definitive answer to how to unlock this vendor's augs? Is it really just PoH/PoF faction? Is it a sliding scale, or once you unlock one you unlock them all?
For that vendor, you just need to do Into the temple (a), Seal of Approval, and Into the temple (b). It might be possible that you only need Into the temple (b) but need the first two to request it. However, the first two involve only hailing and can be completed without invisibility. In other words, they're very easy.
I've unlocked access to that vendor on my alts by simply running them through Into the Temple (b). They still need the other quests to request tasks I assume, but this works for vendor access.