Watch the video, it's very interesting.
But essentially speculation and nothing more, it's described in the last few minutes as a Hypothesis, it's essentially "we have no other explanation therefore possible white hole"
a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.
So no they haven't discovered a white hole, they have discovered a phenomena for which a white hole could be an explanation, with further investigation it may turn out to be something completely different, this happens quite often in science so no, no-one has "discovered" a White Hole!
Edit: As a further note I should point out that neither here or on youtube are any links to scientific papers claiming the discovery of a White Hole, this is essential if you want anyone to believe what you are saying, youtube videos are a dime a dozen.