I'm afraid that there's no way to bypass iCloud lock. Unless you have the Apple ID and password of the original owner, there's no way to unlock the iPhone. An iPhone in this condition is little more than an expensive paperweight.
All of the supposed iCloud unlocking services out there are scams. There is no way to remove the iCloud activation lock without the original owner's Apple ID and password. The service you mentioned is very limited in scope and is reversed if you have to restore the phone.