Timber appeared to seriously foul Pedro Porro in the contest in North London on Sunday.
However, he was not given a straight red, as many fans had anticipated at the time.
Per The Sun, ex-referee Mark Halsey said: "The temperature was rising, the game was reaching boiling point.
"I think perhaps the referee just took the safe bet and issued a yellow card for a reckless challenge.
"Now, listen, when we look at Law 12 (Misconduct) a careless challenge is a free kick and no card, okay? A reckless challenge is a free kick and a yellow card.
"And a challenge that endangers the player's safety with excessive force or brutality must be sanctioned with a red card.
"Now, it's subjective, but for me, I thought they got it absolutely spot on.
"I thought it was a reckless challenge, free kick and a yellow card. I didn't think it met the criteria of a serious foul play.
"VAR looks at those challenges and they stayed with the on-field decision, which was correct.
"I think the fact that he was on top of the ball and then his studs just went into the shin, I think that deemed it a reckless challenge.
"So, listen, on another day, another referee may have just seen it as a careless."