Swamped

"Regrettably, the package contains only half of the truth. I am afraid the misdirection was a necessary measure. For the full truth, seek the other package within the hydra's teeth. May the flame burn bright once again."

The message is needlessly wordy. Makes it easy to crack if you know even a little about how to tackle this sort of thing, honestly. But it's also vaguely written, so maybe they didn't care - in fact, now that you think about it, the symbols were probably more about keeping people from recognizing it as a message if they didn't look too closely. Might have stumped you for a good while if you hadn't seen them before by sheer chance.

Of course, you've got no idea what the "half-truth" in this package was, or where these "hydra's teeth" are. Or, for that matter, why the package was here of all places. You suppose you can work on figuring that out after you block the other latrines.

But then you realize something. The board you're covering the latrine with is made of wood, and the package is a small wooden box. The beetles aren't going for either of them. So something's definitely going on with them... as if the arrow wasn't clue enough.

You might want to resolve that puzzle before you block the other latrines, if only to figure out if you need to worry about blocking them up with wood.