For making a game engine, it can be a blessing to use a more efficient physics framework. For that purpose, it would be awesome to see this tutorial also walk through implementing Nvidia's PhysX.
One of the PhysX libraries for java I found was "physx-jni". Perhaps that can help with your determination.
Thanks for your continued hard work on this Vulkan Book for LWJGL 3. It's been a godsend.