You'd be amazed what you can be banned for. There was someone complaining on here a while back about getting slapped with a ban over macro usage, and there's been several accounts of "witch hunts" for match throwers and alleged hackers. All it a takes is a sufficient number of reports to the support desk, and SE will look into it. Unfortunately, slapping said people with bans is not going to change the fact that they threw a match.
Even hypothetically, if 175 people from the same FC/Linkshell/Teamspeak/whatever all queued for Solo-Feast at the same time, there's no guarantee that they'll get into the same match. Match fixing in this way is very difficult, especially with rank restrictions on who can play with who. That was the whole point of making Solo-Feast a solo queue in the first place, to avoid the same monstrous matchmaking/fixing that happened in WD. This is especially the case because queuing with a team of people is not required to throw a match. All you have to do is queue as a healer and do a crummy job. The only thing a team queue would be good for is if you are trying to tilt the odds in someone else's favour, but seeing as how you can't guarantee that you'll end up on opposing teams, it's not an efficient way to match fix.
Is it possible? Sure. Is it likely? No. It's far more likely that the people who got into a match with just happen to suck at the game or are tome farming. When it happens, it really sucks, but there really isn't much you can do about it except roll with it and hope for better next time. Having SE shoot our queues in the foot isn't the answer. The majority of us shouldn't be punished because of the actions of a few bad apples.