I'm extremely sceptical about any such service. They require your personal information, so they can prove your identity to delete it elsewhere. I get the argument, but this is giving your stuff to yet another organisation.
Not only that.
Imagine the communication between the service provider and the organisation you want your data removed from.
How do you know that the service provider doesn't provide all your identity data to that organisation to identify you, so they can remove your email address. What's to stop the organisation creating a record in their private database with all your details, when previously they had just your email address?
Just because your data is visible with a Google search, doesn't mean that this represents all records pertaining to you. Adding data and sharing it around just exacerbates the issue.
I stay well clear.