Hi CZguy,
You can use Baking Soda ( or fine Walnut 'dust' even better, ) to allow the 'CYA' Adhesive to have better gap-filling ability.
The Walnut 'dust' or other fine inert powder can be worked into the Crack first, use a Business Card edge, say...then, the CYA can be fed into the Crack, and more dust/powder sprinkled on...puff of Air to remove excess powder/dust, feed adhesive again...let cure/kick. Warm is best, where warming the Stock first will aid in the adhesive 'kicking' well.
Some kick faster than others.
Try not to have your eyes right over it when the adhesive kicks...the fumes can be irritating.
Cured overage can be carefully scraped off using a single edge Razor Blade at 90 degrees.
Any Oil or Wax in the crack will tend to interfere with the adhesive binding well.
The crack is in keeping with differential shrinkage of whirled Grain.