I just cut some spalted maple and not having the same thing handy to test, I made an ellipse in the largest area of scrap and tried to cut it, When that did not cut through. I made the ellipse smaller inside, cut the speed by 10, and tried again. After 4 tries it cut through almost as it started to flame a bit, but I was able to use a razor to get the last bits.
In the end this will usually be the case especially if the grain of the wood is interesting, and even if you have it locked down in simple situations, Where there is wood enough to do it I use this…
Depth Adjustments - Beyond the Manual - Glowforge Owners Forum