All reviews are not exporting

I’m trying to export reviews so I can import them on another site but I get no export options to use the slug or sku number yet I get those options when I import.

But, my problem is that when I export reviews for one product, it only exports 4 reviews rather than the 5 I can see exists but then when I import them I only get 3. I had to manually change the product IDs to get those to import.