Yes, Kevin also referred Ilya and me here to help you because he thought it might be some error in your quest data or scripting. Based on your description, however, we told him that it looked like a code bug, and he and Jannik have confirmed it in the mean time.
Regarding the removal of Osiris goals: does deleting it in the editor leave an empty goal behind in your mod folder? That's the only way I can imagine a mod could "delete" a goal that it inherits.
