Ash - Heart Rot

[YosemiteSam]

My neighbor recently took down his large ash tree & there was a piece about 7' long, 8" thick and has a curve that appears to be perfect for a few inches of backset.  However, the heart has some rot in it.  The sapwood looks okay from my untrained eye -- plenty of unbroken growth rings from what I can see at the ends.  Just the heart appears to be rotted.  The hole in the center heart wood is about 1".

Is a rotted billet like this safe & okay to work with?  Or is it likely just firewood with rotted potential?

[Mad Max]

you only 2" under the bark