Oh, uh, sorry I missed this. We usually discuss things like this in the Warframe News and Info thread over in the PC and Console Gaming section of the forums, but I'll see if I can bring a few notes up here.
I can't be of physical help as I'm a PC player, but there are a huge number of questions I want to ask. Such as whether there's a specific element you want, or the nature of this "bug" you mention.
I will tell you that there are a few Frames that can get enough kills to do rank 1 of the Granum Void alone at that level, even without the Xoris (and using the Xoris makes a number of defensive Frames possible for this). I know Mesa is one (the resulting Diplos will be Magnetic-aligned if you use him), don't have a full list of the rest sadly.
I will also tell you that you have to use the highest-tier Crown (the Zenith one) and I wound up getting a lot of those from Sorties that passed through that tileset. I THINK the Hydra or Acheron nodes on Pluto would be your best bet to getting them fairly quickly outside of that.
I... must confess I gave up on getting specific weapons from the Liches and Sisters after two hours trying to get a Lich to spawn one of the Archwing guns. The Tenet Diplos is the weapon my current Sister uses though.
