Remy says "Jack the Ripper was an OB/GYN." Jack's identity is unknown, therefore no one knows for certain what was his profession.
Barnes and Chase suggest that fish processing workers would have the knowledge and expert skill to gut a human and excise specific organs. This is nonsense. Cleaning fish is relatively simple compared with removing particular human organs.
Adding to the comment about Jack the Ripper - it is suspected that he was a physician. However there were no specialists in any area of medicine in Victorian England - or most of the world in thec19th century. The only difference between practitioners until the 20th century was surgeons vs physicians. This was just another lazy, gratuitous bit of disinformation by the Wolf gang.