It's pretty had to tell if an OL was holding or not, unless you see the replays or are at the game live. It's hard to know what Ottawa was doing, but the holding calls that erased the TD were the 'he's running past me so I'll grab his head' kind.
I would like to see them throw Harris or Flanders out on the wide side (for a few plays) when a team is running a zone that leaves it open the way Ottawa was. They would gain serious YAC and force them to cover it.
Which is exactly the reason why Ottawa was my pick to win the GC last year, right after they clinched first in the East. They were trending up at the right time, while teams like Calgary and Edmonton were in cruise control.