Of course had the security guy gone all out the 2 guys from my uni wouldve had a much harder time or been seriously injured. However you should consider the fact that theyre just 2 normal guys. If they were seasoned martial arts users the security guy wouldve been dead. Grappling arts are designed mostly for 1 on 1 situations so heavily relying on it in 1 vs n fights is not a good idea coz while youre trying to take out 1 guy with a say neck lock on the ground the other guy(s) can gouge out your eyeballs or hit your hard on the head or on the nape.