I would drill out the knot, install a hickory plug to within a 1/4" of the surface and then cut a V mortise and make a triangular patch of properly grain orientated maple to cover the hole.
I have done a lot of patching lately on a beat up old TC stock.
Here is a similar V patch (no dowel), I dug out all the cracked wood and cut a V mortise for the patch. This wasn't a one shot deal, I kept working on the angle of the patch, I made at least 6 patches until I had a perfect no gap fit.
End result, doesn't show much. I drilled and installed the hickory dowel after I fixed the crack that started at the lock bolt hole.
This is old oil soaked wood that splintered out when I drilled out the lock bolt hole and installed a hickory dowel.
I dug out the splintered wood and filled the void with superglue and sprinkled sawdust on the wet superglue (it turns into concrete), I had already cut a walnut plug to cover the superglue and pressed it into place while the superglue sawdust mixture was still malleable. Of course my plug was oversized and I cut it down to the barrel inlet contours after everything set up. I matched the stain so it wouldn't show after I took this picture.
I am just a wood hack, there are much better patch fixers here than I will ever be but I thought I would share this for a different slant on fixes.