Here is the problem with this post. While it breaks no rules as you haven't put the person's PSN on blast, you've also enlightened people that they can essentially cause others to not get the quest just by leaving.
I think it's a good thing altogether though because if it's a big enough issue (And it's growing due to the spread of knowledge) Bungie will have to take action and change the requirement to make it to where people can't grief it so easily.
Personally, I think this quest step should be changed. Basing a quest solely on low RNG is a little frustrating and while exotics really feel exotic now. I don't feel that a quest step should have lower chances of arriving than an exotic engram itself.
To those of you that have had luck and gotten the meatball to drop AND killed it, congratulations and I hope you enjoy your gun.