The subject is not me, by typing a few words can you really access a private wallet with this site? for example, I typed you it gave me a private key with an account which has a zero balance, but if for example someone were to type a correct word can they really open the wallet in question?
What is happening here is just auto-generation. Copy your original private key to your main wallet, change a few words and numbers from the same private key, use it to import into a wallet, and you will see you just got yourself a new private key with an empty wallet.
A private key can be generated from anywhere and will be valid, provided the number-world combination is correct, but it will always lead you to an empty wallet.
What they are doing, in my opinion, is just a wallet gesture.