What are the reliable ways to justify to a third party that the inventor of an USPTO granted patent (i.e. linked in google patents) is actually me (given that I am the real inventor)?
The inventor of an USPTO granted patent can provide a patent certificate.
From https://www.upcounsel.com/patent-certificate (mirror):
When Will I Receive My Patent Certificate?
Once your patent application has been approved by the USPTO, you'll receive a Notice of Allowance. Then, you must pay your issue fee before subsequently receiving your Issue Notification. The patent certificate with the USPTO seal will be mailed on the issue date.
If you have designated a patent attorney or agent as your power of attorney, he or she will receive the certificate as the attorney of record and should forward it to you. If no power of attorney has been designated, the intellectual property (IP) owner will receive the patent certificate at the address indicated on the application datasheet.
The Certificate Series plaque is a reproduction of the patent certificate. Extra patent certificates can be ordered from USPTO for $25 each. Each patent certificate contains the USPTO seal and director signature; you can also request it to include the names of the inventors and a corporate logo at no additional charge.