To be fair to Alan Young the Northampton defender certainly handled the ball for the Leyton Orient penalty. It was a pity that Young missed the shove in the back that the defender received in that incident.
I was at the match, watching with interest.
He appeared blindsided for the 'handball' that lead to the penalty so was unable to see the push in the back, that caused the handball, which is shown clearly on the video.
Prior to that, early in the first half he could/should have red carded a Leyton player for very serious foul play instead of just a caution. It probably fell, wrongly, into the "too early" category which didn't enhance him with the crowd or players.
Regarding the red cards following the penalty, having seen the footage from behind the goal it appears that our player forcefully attempted to retrieve the ball from a home player who was running away with it in hand. Another home player came in at speed and 'rugby tackled' our player into the advertising hoardings. Obviously a melee occurred, which looked mainly handbags but our player and the rugby tackler were red carded which was probably a justifiable sanction.