maybe this only makes sense to me but please consider reordering a couple of shadowglen quests.
currently gilshalan windwalker offers 3 quests total
1. webwood venom: collect 10 webwood venom sacs, turn in to get part 2
2. webwood egg: collect egg inside shadowthread cave, turn in to get part 3
3. githyiss the vile - kill the named spider inside shadowthread cave
logically 2 is available after 1, but 3 requires that the quest "iverron's antidote" be turned in to iverron before the third quest is available, which means you run back to shadowthread cave to kill a named npc when she could have been killed in combination with the second quest. the third quest githyiss the vile is not available until after giving iverron the antidote from quest iveronn's antidote, needing a run back into the cave you just got an egg from.