You can download original firmware from here
https://www.techpowerup.com/vgabios/ just choose the exact model of your card like the listed below.
GPU Brand:
Card Vendor:
Card Model:
Bus Interface:
Memory Type:
Then reflash it to your RX470 card it should be work as a normal and I think there is a switch for RX470 where you can just slide it to the right or left to switch it to default bios firmware where you can play normally.