Thanatos, you're seriously putting too much though and worry.
YOU ARE TOTALLY ENTITLED!
You can say the truth if you like: "It appeared as if the figures hand would extend further and I applied the tiniest bit of pressure and it snapped."
What I would recommend doing instead though is buying a 2nd Lockdown first and making sure it's all good, or piece together one good one between the two. Then take the remnants back and simply ask for a refund saying that you find it unacceptable that a $25 toy could be so poorly made. That way you don't risk getting a second bung figure.