That is easily explained.
If there are lots of shares at the ask, the buys won't move it. I think sombody is wishing they tried to buy at bid. There are still no sellers, as indicated by the action. The 5k was a test of the bid strength, probably by the same guy who bought the blocks, or just one MM testing the other side. These guys play too many games, and only a broker or MM can test the strength without paying the commission on the trade. It sucks for us. They can prop it up with 5K shares, or have 2 million shares at the bid, and only show 5k.