You think they didn’t make sure the game was square?
The developers of the game? I’d give it a 50/50 shot, how many times do people get so enthusiastic about something that they are more worried about doing it rather then whether they should be doing it? Maybe they are Pokemon fans that saw a big market and weren’t happy with the quality or output of Pokemon games. The company that made the game is called Pocket Pair and seems to only have 3 games:
If nothing else the creatures are very similar and it’s impossible to know how a court would rule on that. The line between infringement and non-infringement can be blurry and hopefully Pocket Pair is prepared to defend their content.