Sports direct bought most of the shares before the stock ran up. Look at their 13D filing. They were buying shares from pessimistic sellers. Buyer only move the stock only when there is a consensus of the state of affairs and often no buyers are needed to change the bid, news itself moves the stock price without a single trade.
Not sure what it's weird to have 20% of shares change hands and the stock not move up a large amount. Apparently somebody was willing to sell the shares for about the same price a buyer would pay. Stocks move up or down when there is a consensus of the near term outlook. The collective knowledge has been split on the state of affairs. Resolving the refi of the debt and resolution of the SEC investigation would be a consensus event.