I beat it at at level 53 with 2 friends, but I didn't attempt it till then. I was busy pursuing other quests. It may very well be that your legendary friends were focusing on other things and just hadn't gotten around to it.
You are allowed this quest once you reach level 50. I am sure there are plenty of players who were able to complete it at 50 or 50+
Briskbreeze is easy, compared to some of the others. Personally, I didn't even attempt it until long after I'd hit level 60- this is mostly because I'd expected it to be more like Waterworks (thank goodness it wasn't) and thought that I'd need a group to complete it (I didn't, but it was more fun with one). Therefore, it's totally possible to complete at level 50-odd... Congratulations!