I really think that these are just attempts by taxidermists with no idea what they were trying to replicate or just an unfortunate lack of skill. The hippo with the oversize dentures and the teeth of the lion(?) are..odd.
Reminds me of a story from about fifteen years ago. Mr grandsons were always joking around and would come up with goofy stories to scare their friends. They had this little neighbor girl scared to death of the chupacabras. They had her convinced they were in the area. She wouldn't come out of the house except to go to school. Her mon and dad made a visit to see my grandsons one night in front of my daughter and SIL. They had a hell of a time convincing the little girl otherwise. The grandsons lived hard after that one.