That interview is most probably fake.
How can thebitcoinstrip find out and contact Hufflepuff when stunna himself couldn't even after putting a bounty on him?
In theory, hufflepuff would have reached out to a member of the media who would interview him. I am not sure why hufflepuff would have reached out to someone at that website though. It would be very unethical for a journalist to leak information he agreed to keep confidential with a source.
The author of that article should have received some kind of proof the person he was speaking to was in fact hufflepuff before he published that article. A signed message would have been most appropriate.