A few GAFers tried earlier but didn't get loot again. There is a theory that the fireteam leader needs to have not done the raid yet for it to work. But I don't think anyone here has confirmed that yet.
I haven't touched the raid (other than the first chest) so I am willing to try it if there are others interested.
Just saw in the comments that they did the raid before the weekly reset, and then did again right after the weekly reset. Hence the "double" drop.
Although, that doesn't explain not getting anything in the chest?