The French-Algerian had been booked for an off-the-ball incident with Airdrie striker Jim Lister in the second half and he was pulled away by a team-mate after the final whistle as the teams left the park.
Rangers boss Ally McCoist, whose team won the Scottish League One clash thanks to Lewis Macleod's 20-yard strike in the 18th minute, said: "Bilel received a second yellow coming off the park. I wasn't there, I was up the tunnel, but the referee told me he received a second yellow for acting in an aggressive nature."
Mohsni was angered on several occasions following challenges from Airdrie players, who had five men booked, while Rangers midfielder Ian Black was also cautioned for reacting angrily to a tackle.
And McCoist felt there was a hostile atmosphere in Lanarkshire and during their 4-0 win at Dunfermline on Monday.
"Whether I think it's over the top or not, I think it's just something we are going to have to handle," he said.
"There was an attitude around East End Park and around the stadium tonight which I don't think is necessarily a good attitude for women and children to be involved in at a football game.
"Let's just leave it at that. But if we're going to have to handle it that way, we are going to have handle it that way.
"I'm a big enough boy and have been around Scottish football long enough that the fans and opposition aren't going to open the door and let them trample all over you. That's just the way it is."
Bollan had little to say about the post-match incident with Mohsni.
"I was just trying to get my players off the pitch when he gave me a mouthful," the former Rangers player said. "I have no idea (what it was about)."
And Bollan defended his team's approach.
"We needed to let Rangers know they were in a game," he said. "My players did that.
"I told them they would have to be in their faces and let them know they were in a game. They did that, they battled away great and I'm extremely proud of them."
The bottom club almost snatched a point with some late pressure. Gregor Buchanan sent an overhead kick just wide and Cammy Bell saved brilliantly from Willie McLaren before Mohsni cleared off the line.
McCoist said: "We should certainly have been in a more comfortable position after an hour or so but when you don't do that you run the risk of the opposition throwing people forward in the last 10 minutes, and I thought Airdrie did that.
"But it's a great three points away from home, and I thought a deserved three points."
Bollan added: "We created chances that we haven't done in the past against Rangers and had a couple of extremely close ones.
"We showed we were looking to take something out of the game with the subs we made, we had maybe five attacking players on and we nearly salvaged something. I think we probably deserved a draw."