The purpose of the 4th timeout is when a team does not have anymore timeouts and is on defense, if they have an injury during the play, they are granted a 4th timeout. And subsequently after, the clock starts with 40 seconds. This is so they don't benefit from their own injury by getting a stopped clock. What happened here though was the Bills player got hurt and tried to play through it after the play and to the next. After 33 seconds of play clock he went down. I don't know what the rulebook says but logically, they should grant the 4th timeout and then have the play clock start at where the offical stopped it. Otherwise, they are bastardizing the rule for what it was not intended to do. Really stupid. The Patriots should have had to punt with 20 seconds left.