As shown above, both of the items from this quest does not drop from Stinger Venom[1], but instead exclusively is rewarded from Stealing Back The Mushrooms[2]. ATT does list both as a source, although only Stealing Back The Mushrooms rewards it.

[1] https://www.wowhead.com/quest=9830/stinger-venom
[2] https://www.wowhead.com/quest=9709/stealing-back-the-mushrooms

Fixed on Git, thanks for the report!