A deciding rule to tell whether some chemical or plant is an addictive opioid: if people are using it to "lessen their withdrawal symptoms from opioids".
It's an opioid. (Or rather, contains opioids—more than one, by the way!)
Every purported "non-addictive opioid substitute" in history has turned out to be an opioid. If it acts like an opioid and quacks like an opioid, assume it is one.