I wouldn’t jump to that conclusion — the first and last names are not uncommon, and the GitHub user has some attributes (eg Haskell; geographic ties) they do no

I wouldn’t jump to that conclusion — the first and last names are not uncommon, and the GitHub user has some attributes (eg Haskell; geographic ties) they do not share with the LinkedIn profile you link. Unless you have strong evidence of their identity I’d suggest rethinking this.