This utility is still in beta phases and the accuracy cannot be guaranteed at this time. Pick the creature type from the list, put in the number of times it has been tamed, and your displayed taming skill.
Keep in mind that each taming attempt is independent of the next. Multiple taming attempts do not increase your chances for success, they simply decrease the probability of failure, similar to rolling a dice.
The script is doing a check against the taming requirement of the creature, not its name. Many tameables have the same minimum requirement. The script says to display all tameables with that requirement, but your browser is forced to pick one, which is usually the last one in the "selected" group. Some newer browsers may highlight all creatures that fall into the "selected" group in a different color.