[Mister Ed]

I'm pretty sure the Doberman would apply to this attempt, but I don't have the card, so I can't be sure.

However, I'm not even sure if the answer to your question is relevant at this point. It doesn't sound like this situation is likely to be solved by being able to say, "Yup, it turns out I was officially right."

If it were me, and there was any question about what the answer was (i.e. if the answer isn't clearly stated in the rules on hand, and I hadn't already seen an official ruling), I'd err on the side of the least nasty consequences, but tell them I'd ask for an official ruling for next time.