I'm at a loss for what to do next. On one hand, we could attempt to exploit Whistler, but I don't know if it's really the time to do so yet. Also, the man's terrified. There's no guarantee that he'll step that far out of line against KS, no matter what he feels about them. I don't think he's expended his use as an informant yet; there's no need to make him a saboteur.
On the other hand, Aether told us he'd be back soon in the same communication that told us about the Oracular Eye. If we wait for him before we move, he might be able to give us something to set us on to the next step. However, he may be waiting for us. In the end, we might just end up wasting time.
On the third hand (I know that's not how this figure of speech works, but I'm doing it anyways), we could attempt to go in a completely different direction and search for an opening elsewhere, although the probability of that actually working seems extremely low, so please discount this third hand option immediately. It shouldn't even be here. Humans don't have three hands.
TL;DR: I have no clue what to do.