That was only a blog post about a secret draft that has not been published, nor peer reviewed. Let's classify it as "unconfirmed".
As for Linear A decipherment claims, claiming decipherment isn't the same as decipherment. For example, here's a claim from 2014 that Linear A encodes spoken Japanese: https://konosos.net/2014/12/09/the-phonetic-method-in-linear... Does Linear A encode spoken Japanese? of course not.