You usually can’t tell reliably from a single front photo like this. On a twin-lens reflex camera, the upper lens is the viewing lens for the waist-level finder, while the lower lens is the taking lens that forms the image on film. In the provided photo, focus appears to be on an area above the top lens, so the lower lens is too out of focus to judge its condition. That means you can’t confidently confirm haze from this image alone.

If haze is in the upper lens, it mainly affects finder brightness/clarity. If haze is in the lower taking lens, it can reduce contrast and image quality. Because the listing avoids clear close-ups of the lenses, it could simply be a poor photo—or it could be making the condition harder to assess. Ask for sharp close-up photos of both lenses, especially the lower taking lens, before buying.