How about the following translation: "Ho la sua forchetta nel mio piatto." Is it correct too?
Yes, the only difference is that it shifts the reader's attention to the fork instead of the plate, but it's such a tiny difference that I don't think duolingo should enforce it.
holy cow that was a tough one!
For your information, the alternative: "Ho la sua forchetta nel mio piatto" was not accepted by the system. It's still correct though.