Ima pretty sure Minato was undoing his own seal dudeEh it was ok. I think you were too eager to make a new prediction. You should've given it more time. Naruto's Eight-Trigram seal is gone. The seal was broken when he learned to control the nine-tails chakra. So Minato wouldn't go to the battlefield and release it. Also Kurama's other chakra was sealed along with Minato using the demon-death seal, which was also broken when Oro broke it in order to bring Minato back.
The part where the kages enter the battlefield also seems a bit uninspired.
It's not a bad prediction like I said I think you rushed it. If you took more time to think about it would've been better. I'd give it a 3/5