Bummer. You got to get under them. They like to tunnel sideways in the heartwood and they can only get so far before they mature and head back out.
I pretty much stopped storing osage with bark and sapwood on, even inside the shop. I bite the bullet and get 'em all chased to a ring and all the sides and bellies cleaned up. Easier to store and no risk of bugs that way. I've lost a heap of osage in the past to the li'l SOBs. I spent Sunday going through all my osage, some of which is 10 years old, and doing the same to it. I had one piece in there with bug damage.