In short quite the opposite. The skull fragment was conclusively prove not to be his, but that is less an issue than it sounds as it was always in question. It was the jaw piece which was proven to be his, based on dental records. For more on this, check here: https://www.reddit.com/r/AskHistorians/comments/4pc0pk/did_hitler_really_survive_until_the_90s/d4jqb5b/