I am just browsing here, and I know nothing about items like these. However, it seems to me that the tail fluke of Nemmie's whale is added as separate pieces. Carol's whale appears to have a fluke that is pulled out of the body glass. Also, the eyes appear to be of different style and size and the main body of Carol's looks to be larger, in proportion to its tail section, than Nemmie's.
Does that help or not? Like I said, I am just browsing.