Sooo, I tried my theory. I rolled back before the Weisshaupt mission and defeated the boss for the "Heart of Corruption" Quest line, /then/ I went and completed Weisshaupt. I got through it all and completed the conversation with my companions at the table at the Lighthouse. Got to my character again and... Saw no loop on my Rook's hip. I feared I'd redone all that for nothing, but I went and tried an altar and... It worked. Even without my loop/dagger. I tried a wolf altar next, then a special chest, then a special wall break, and they all worked even though I had no loop. I saved and reloaded and the loop was on my hip again. When I did the Weisshaupt mission previously, the loop appeared automatically right after I talked with my companions at the round table back at the Lighthouse, but this time I had to save and reload.
I don't know if it's going to stay working and again, I don't know if most people would be able to finish the "Heart of Corruption" Quest line without the experience/weapons you get during Weisshaupt. I definitely cheated and boosted my stats because it was a lot to replay through (even with the cheats) just for the sake of testing the bug. But... Yeah. As of right now, I have both quests done and my loop, so... -insert me shrugging here-
I've got this thread bookmarked for updates and I will come back if my loop/dagger disappears again. So, I don't know if everyone can, but try to finish the "Heart of Corruption" Quest, /then/ do Weisshaupt, and you may have your dagger/loop back and not immediately lose it again. You just may have to save and reload in order to see it.
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