Midway through the first half, Hoops stopper Gordon raced from his box and fouled County’s Jackson Irvine after the midfielder had rounded the Scotland international.
However, Collum only showed Gordon a yellow card much to the despair of McIntyre and his players.
“I think the interpretation is a clear, obvious goal-scoring opportunity,” McIntyre said. “For me, if Jackson stays on his feet, he’s got great speed of movement, then he’ll be able to wrap his foot around it.
“If it was at a tight angle, I could maybe understand that, but from our point of view we are really disappointed with that decision.
“I think when you freeze it, (Virgil) Van Dijk is still outside the box. It is hypothetical because we will never know, the referee has deemed it not to be obvious so he has not given it.
“We are disappointed with that because we felt it was a big moment in the match.”
Gordon went on to make some important saves in the second half despite Celtic ultimately easing to a fairly straightforward win, but McIntyre was happier with his side’s showing after the interval.
He added: “In the second half, we asked the players to show more belief, especially in the final third, and get bodies forward and Craig Gordon has had a few saves to make, so a far better performance second half.”
Ronny Deila said the second 45 minutes of Celtic’s opening-day win was “one to forget”, but insisted his players would be ready for their midweek trip to Baku to play Qarabag in the second leg of their Champions League third-round qualifier.
“I think first half was an okay performance, second half was messy and not very good,” Deila said.
“We were too open and were very sloppy with the ball as well so it was a half I want to forget. I’ll take away the first half and also the result.
“There are always some positive things; KT (Kieran Tierney) had a good game, and that was positive. Kris (Commons) came on and also had some good play. We have to take the positives with us but there is also other things to do better.
“It is a totally different game (against Qarabag) but the players know what is coming up so we are looking forward to that game.”