That makes a valid confession actually. As long as the priest is able to understand the specific sin it counts.
I don’t think what the Pope said there is heretical.
The last Sunday of my tour in Thailand, back in 1963, I wanted to get to Confession before making the flight across the Pacific. I entered the Confessional and asked, "Do you speak English?" I don't know what the priest said, but it definitely wasn't in English. I spoke a little Thai, and I think I'd have recognized a reply in Thai. It sounded more like Chinese to me. Anyway, I realized I wasn't going to have a chance to make a confession, so I just left the Confessional.