Im a bit at a loss here.
My code seems to be just the way the docs let me to believe it works.
Hovering over tiles returns a null object tho
Printing mouse and tile position reveal reasonable numbers too:
print("Mouse Position:", mouse_pos)
print("Tile Position:", tile_pos)
Mouse Position:(386, 154)
Tile Position:(3, 2)
Mouse Position:(386, 153)
Tile Position:(3, 1)