The "back checkers" were coasting down the ice within a stick length on either side of the puck carrier, not 20 feet back. It's pretty inexcusable that neither bothered to engage. Steel in particular, since he was on Lockwood's forehand side, and the side that Lockwood beat Mete to. If Steel engages, there is no one-on-one. There probably isn't even a shot on goal. He easily could have. He just didn't.
Guess we all have our different standards. My coaches sure as hell wouldn't have been blase about a one-on-three turning into a one-on-one.