I spam floor 2 but i don't use any modifications or smash files or whatever you guys do. No matter how hard I try, i still don't get great pets or even perfect pets. Perfect pets are 1 in a Quadrillion or a trillion and I absolutely agree with @Mr_Scooty , a player who played for virtually 2 years and counting. I played very many hours a day at one point but even then, I'd never get such pets. 5 eternal pets in a year and only 1 or 2 actually are good.
Sometimes i had days where i played 6 or 8 hours a day but regardless, the chances are still very small for such eternal pets just dropping like that.
The chance of even 1 perfect pet in eternal form should be very miniscule that only 1 or 2 of the 5 million players who downloaded should have got it.
If GOB did get it by legit chances, then they may have shared it. Or they may have used the upload and save trick on devices many times until they get the pet they want and share to other people.