I'm not sure what the relevance of the existence of anomalies in game play would be here. I literally just explained that ROMs can be modified in a way not detectable solely by viewing the game play. And we have no idea if it's the official game or not, which is the point. It's a third-party multicart that was manufactured by a shady individual with ties to an illegal IP-stealing company with a sordid history of hacking ROMs and releasing them to the public. Moreover, I can bet that Ulisses did not contact the manufacturer and request the MD5 of the Kangaroo data on his specific 480-in-1 cart. In the off-chance he did, I would be that they didn't answer.
Again, if one wants to play Atari 2600 titles casually (or titles on any other platform for that matter), then these XXX-in-1 carts are great. Conversely, if one feels so strongly about getting recognition in a competitive environment by a community whose entire existence and purpose is competition, then one will have to do better than use something other than *VERIFIABLE* original hardware/software. If one cares less about recognition, then be satisfied with a reject.