I'm always suspicious of people who claim expertise/special knowledge but aren't quick to offer it and instead engage in petty back-and-forths. Instead of trying to win this debate in the narrow sense, why not just make the best argument you can in support of your position? If authority has any value, it is because it gives you specialized knowledge that lets you judge the likelihood of speculative scenarios better than laymen. If you can't communicate that knowledge and the argument that leads to your conclusion, your supposed expertise just isn't worth much in this context.

My argument was that it is reasonable to be concerned that human terrorists might use AI to assist with building bioweapons.