Anyone can publish an article about a historical figure claiming something has been “proved”, but without disclosing the scientific procedures involved, no one is obligated to believe it.
Yet, you're willing to believe something, someone claimed back in 1945.
Anna Anderson (born Franziska Schanzkowska) claimed she was Grand Duchess Anastasia of Russia, and the myth lasted for years. When they found and dug up the partial remains of the Romanovs, they sequenced their DNA, and compared it to part of Anderson's intestine that had been stored since surgery in 1979. They were able to extract her mitochondrial DNA for comparison. It didn't match. They also recovered strands of Anderson's hair that her husband had kept, and tested it. Again, the DNA did not match. She was simply a nutcase imposter.
Yeah. Like claiming Adolf Hitler flew out of Templehof for ‘’La Vida Loca en Brazil’’.