There was one developer helping make Blender work with Corona. However he was doing this off his own back and completely for free which is amazing! I can't commend him enough for what he has done.
However, he has been unable to support the addon for the last few months which is completely fair. He has a life too of course.
Corona are not willing to support the Blender addon themselves... Even though renderers like Octane and Vray do have good support and come with with preview rendering.
So no, Caustics is not working with Blender and not in the foreseeable future.