It’s a strange comment, which could only mean 2, in my view. But the perfect infinitive would be more idiomatic: She can’t be a fool, to have said that (= if she said that).
The sentence is not an acceptable communication of either possible meaning.
Based on your suggestion #1, are you really thinking of the common expression "not fool enough to [do something]?
In this case:
She is not fool enough to say that.