YFI crashed towards $12,000 on Thursday and unconfirmed evidence shows that Sam Bankman-Fried was behind the plunge. A Weibo-based profile, operating under the pseudonym of “Crypto Apprentice,” published a string of screenshots that connected the FTX crypto exchange CEO with the YFI’s massive price meltdown. Per the images, Mr. Bankman-Fried deposited FTX’s native token FTT…