I've resolved this quite nicely. The solution is actually very simple, just unconventional.
The graphics are depth sorted via a TreeMap, and then rendered to the screen. One can simply traverse this TreeMap in reverse (and keep it until the next render cycle) to translate the cursor location to the proper image it falls over (by testing the pixels [in reverse render order] and checking if they are transparent.)
The solution is in the open-source project, under the io.github.jevaengine.world.World class, pick method. https://github.com/JeremyWildsmith/JevaEngine/blob/master/jevaengine/src/main/java/io/github/jevaengine/world/World.java