I can see you confusion - I still believe that the singularia is actually the FINGER LEATHER CORAL. As I own two. AND I used to own a cabbage leather coral - and they are DEFINITELY NOT THE SAME....
Another thing - lobophytum corals in my books have very small mounds for "fingers", and is usually an "encrusting" type of leather coral, meaning that it grows low on the rock, unlike sinularia that grows upwards like a tree, with a single central stalk/base/foot....