Then it got into a conversation about girth. I said to (the guy above) if you find someone who is 6.5 or above same deal, he said “What about 4.5”, and I said “why is that what you are?” he nodded his head “yes” and talked about it as if it were pretty girthy. Again other girls have said he’s got good girth, and he’s kind of acknowledged he doesn’t have length, at 5’4. I would bet he’s probably 4.5-5X4.5 . I also would have guessed girthier after seeing it flaccid.
Back to the op, one thing to keep in mind is the fact that (most?) women realize penis size is an issue for guys. If he’s at low-average length she can’t really lie about that, but girth is a value that has far less public understanding. So she’ll change the subject from length, and comment on something that seems at least plausible.
It’s kind of like a girl asking if an outfit makes her look fat. You side step with “It makes your legs look nice” and hope she doesn’t realize you didn’t answer the question.