modlauncher bypasses mod classloaders for everything under the org.lwjgl.* package, so it doesn't recognize Yoga so it doesn't find Yoga. Currently this can be mitigated in the development environment by including yoga on the classpath, but that's not a final solution.

This is currently waiting on McModLauncher/modlauncher#27

f8fcadb removed Yoga, since it wasn't really worth the trouble. A cool experiment, but not very practical.