He still thinks that "I don't know" is a bad answer to a "yes" or "no" question.
Oh, but by all means, you have repeatedly done the same. When I pointed out your hypocrisy, you ignored it. Of course, as you have noticed,
this is yet another example.Did you stop beating your horse today? (I don't have a horse, and never did.)
No, I didn't stop beating my horse today. I never started doing so to begin with. The reason for that is that, much like yourself, I do not have a horse.
Do you think "I don't know" is the answer here? Like, "I don't know if I am currently beating a horse, since I do not have one"? Yet again you fail miserably.
Is the Mandurian word for "house" the same as the Thai word for "bed"? (I don't speak either language and don't know.)
The answer is "No". There is no Mandurian language, therefore the Mandurian word for "house" doesn't exist, which makes it very different from the existent Thai word for "bed". Possibly you meant a local dialect of Italian spoken in Manduria, in which case the answer is "no". Alternatively, you might have meant Mandarin Chinese, in which case the answer is still "no".
Of course, "I don't know" is an existent answer to the second question. However, using it in a debate doesn't strengthen your argument, especially when a sufficient answer is a Google search away.