if it works it proves that it is indeed an original ps2 game and since info about these versions is so scarce they might be something realy special.
if they are fake its nothing special or anything but if they are original they might be something relay rare and amazing
and pirate copies on the ps2 dont work on an unmodded ps2 thats the thing:)
home made pirates do indeed not work on original consoles unmodded however if it is semi proffesional, wich were sold in the past it will work on original ps2 consoles unmodded or not.
also if you would like my opinion, I'm pretty sure these are fake unless the discs are the same as the legit copies. also if it is semi proffesional it can have some things wich cannot be done on home made pirates since they had the right tools and a factory to produce these, you cannot compare it to home made pirates.
There are no different versions except for promo's + the occasional demo disc and if were talking about value disc only ain't that great plus magna carta can be bought in europe wich isn;t to expensive to be fair.
also I'm not trying to get your hopes down but the chances are pretty high for it being fake and to top it off the reward ain't to great. you could just play these games on an emulator or just on these pirates if it's just for the gameplay.