>>43527694let's not forget that Jurassic Park also introduced the idea of genetically engineering damaged DNA with genes from other species in order to "revive" them. I want to say it even introduces the idea of a disaster caused by this approch, not too dissimilar to what's supposed to happen with Mewtwo in game.
I don't think you directly got a Mewtwo out of it like with the fossils though. This is all speculation but I think it might've been the trigger to open the burned mansion, which might or might not have been burned beforehand. It does revive Mewtwo but you don't get it, instead it wrecks some place and escapes. It kinda fits with how Gen I did things, too (locks you out of a lot of things unless you give a specific item to someone)
I don't buy the story about Morimoto sneaking Mew at the last minute, there's a lot of mentions to Mew by name in the source code, so I think it might've been cut at some point and then readded by Morimoto, rather than completely created from scratch and added in secrecy by him. There's a Mewtwo and official artwork by Sugimori for it for fuck's sake so the rest of the team must've known at least about its existence.