Debating is not AOC's strong suit; it's not Shapiro's either, but he at least plays at it a lot of the time so until he runs into someone who knows what they're doing it can look like he's winning. Shapiro is a master of playing quickly to his side's preconceptions and blowing past any difficulties so fast that you just get the feeling that he's really on target. So you shouldn't "debate" with him if you don't know how to debate well, and also know the subject matter.

But Dawkins is a perfectly fine debater, and is happy to debate religion, and has done so many times before with many people (sometimes coming out looking very good, and other times less so). He's just not happy to debate Craig because (1) Craig is being a pain about it and (2) Craig has defended sufficiently abhorrent viewpoints that Dawkins would rather not engage. I do take him at his word on this: https://www.theguardian.com/commentisfree/2011/oct/20/richard-dawkins-william-lane-craig

I don't know anything about Super Mrs. C, but I do know that not engaging with your points is not a particularly bad example of intellectual dishonesty or cowardice. It's ambiguous. Why did she not feel like engaging? Well, maybe you have good points and she's wrong and doesn't want to show it. Maybe she wasn't in the mood. Maybe she's so convinced of her rightness that she believes that any other engagement is just a waste of her time. Maybe she's guessing that people who disagree are so set in their ways that a debate is pointless. Maybe something else. Is it to her credit? Well, no, it's not.

But you can't tell it's cowardice, and you can't tell that it is because they are wrong. And anyway, what's the harm in having your point up there, unanswered? Unless you know you're wrong and need the other person to be fooled and admit that you're right, other readers can read your comment if they wish, and make their own decisions.