IMO this was the result of fans coming after it started, not being aware the tribute was going on and one or two shouts from the stragglers- who shut up as they were made aware to observe the silence.
Some Dundee fans felt this was disrespectful for remembrance silence and reacted. The huge majority of both fans then took it upon themselves to quiet others down - which happened. It was not an organised disturbance of the silence and both sets of fans should be commended for taking it upon themselves to ensure the remainder of the silence was observed.
Not surprisingly the Daily Record has made this their Derby headline. This will allow them to deflect the expected organised chanting during remembrance silence from Celtic fans.