I would differ as the scene is quite ambiguous. There is no certainty as to what exchange, if any has taken place. There is a rather vague connection made to what I saw as "boredom - resignation on the parts of the two players but there also may be a reaction. The guy on the right might have called the other one a name and the gocart guy has responded with a look of contempt...anything could be taking place; thus we have ambiguity in its fullest measure.
Now I understand why you all think these photos are "ambiguous." Your concept of an ambiguous photo is one in which you can imagine various story lines to apply to the people. He might have called her a slut, she might have said let's have sex, he might be arguing with his boss on the phone, or she might be arguing with her mother, she might be talking with the pope, and so on, and so on. Therefore it follows, that
any photograph involving a person is ambiguous, because we can invent multiple stories of what each is doing, saying, or perhaps thinking. As you put it, "when there is no certainty of of the exchange."
Photographs do not contain a sound track. And therefore no certainty of verbal exchange. When viewing photographs we have no expectation of any kind that we "know what people are saying," let alone what they might be thinking or feeling. Therefore it is a given that any possible words can be put in anyone's mouth or thought bubble on any photograph taken that includes a person. That general claim eliminates the possibility of declaring one photo ambiguous and the other not. I can invent "multiple speaking roles" for any photograph I take with people.
I think your comment represents a big misunderstanding of what make an ambiguous photograph. Ambiguity isn't about making up countless variations of stories for the photograph. It is about the photograph driving in two (or sometimes more) basically divergent directions based on the photographic content - not some imagined verbal content. Your photo of two men is explicit in content - "two men on a walkway are looking at each other." Each man is explicitly rendered in their circumstance. The space and time they occupy is explicitly rendered. You don't turn that into an "ambiguous photograph" by simply speculating on what they are saying or thinking. That aspect of any photograph is it's "story telling ability" or it's intellectual content. That's what is meant by intellectual stimulation of a photograph. It might also refer to the emotional impact of a photograph. If it makes you "feel" a certain way, say, pitiful or angry, that's the emotional content. Neither of those defines an "ambiguous photograph." To say every expression people have on their face is "ambiguous" might be true, but also meaningless in the sense we are discussing here about photography. It's easy to say all expressions are ambiguous in a photograph. So, that makes every photograph ambiguous? No, it does not. It might make some mysterious, or humorous, or intriguing, but not ambiguous.
I am glad you spoke forward because I simply couldn't see where all this claimed ambiguity was in these photographs. Now I understand what you all meant. You invent mental scenarios and scripts for your images, and since you are then "uncertain which is true" it becomes very ambiguous. I get it - thanks.