This is my personal opinion, based on personal experience. What the dozen young men did was vile, regardless of the young woman's consent. I can empathise more accurately with the men because I am a man, I am heterosexual and I was once their age. I have consumed alcohol and drugs at their age, I have been on lads holidays in Magaluf. I have had sex with strangers I have literally just met in a bar under these conditions. There is no way I would be in a queue with 11 of my friends, waiting for my turn to sexually interact with a drunk teenager, and not question the acceptability of what was going on. My very first thought would be to question the capacity for decision making with regards to the teenager involved. Were drugs and alcohol influencing her judgement? Mental health? This is all on the assumption that the teenager was consenting - if she wasn't, then clearly it's a no brainer.
To be clear; I am saying that these men were not victims and that's regardless of the consent from the teenager involved. It was abuse of a person, abuse of their position and anonymity within a gang of youths. It was taking vile advantage of a situation, and it was unacceptable. They sailed so close to the realms of acceptability that consent could arguably be considered impossible in that situation. They are getting a free pass here, and I'm calling it out.