Reinstalling Ventura on Patched iMac (Help!)

Hello! So I’ve been trying to reinstall Ventura on my 2017 iMac (the latest version of Ventura it supported) I was having issues with the internet recovery and erasing the disk fixed that but I was having internet issues. So now I just have the Ventura Install on an external SSD, so I’m just trying to boot and install from that.

I’ve gone into recovery and checked it’s mounted and detected and it is, it is formatted correctly too.

When I get to the screen to select the drive, it doesn’t show it. Please help! As I want to sell this iMac