With the gun pointed at his leg. Also it appears to be unintentional- he was pressing the Serpa and paddle and the when the gun came all the way out, his finger slipped onto the trigger.
Why I don't like "trigger finger button release" holsters. Too easy for your finger, already tensioned to push da button, to slip onto the trigger and, "POW". And since most of the time your other hand is crossing over to grab it, there is a good chance you'll hit a booger hooker if you miss a toe.