Yeah, Violet can help, since she wasn't doing anything else that would take up her attention.

In total, Astra is able to gather enough herbs to make three doses of her poisonous concoction. Also, if you want to give it a name, you're welcome to do so. For reference, the poison's mechanics:
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A creature subjected to this poison must succeed on a DC 14 Constitution saving throw or become poisoned for 24 hours. The poisoned creature is unconscious, but wakes up if it takes damage.

This is a contact poison that affects any creature that touches it.