Mac Pro 5.1 not booting and prohibited sign

Hello! Seeking some advice on how I would fix this issue I’m having with OCLP on a Mac Pro 5.1.

Followed the instructions on GitHub and was initially able to get into the OCLP boot menu by holding option during boot. I chose the drive to install macOS on and then tried to install macOS using the USB method with EFI boot. When the computer restarted, it went to this screen (see pictures). If I powered off the computer and then held option during boot, this menu comes up but if you tried to choose either of them, it goes back to the prohibited sign from earlier. I’ve tried resetting the NVRAM to no avail as well. Can’t even boot into recovery mode as it’ll just go to the prohibited sign if I held the key sequence. I also have tried to see if Internet Recovery would work (both with wifi and ethernet) but no matter the key combination, it goes back to the prohibited sign shown below.

I do not have another mac to remake the macOS installer.

Not sure what to do at this point.

My Mac Pro 5.1 has 2 Xeon processors and 48GB of RAM running triple channel. GPU is ATI Radeon HD 5770. Currently have a 1TB HDD and a 256GB SATA SSD installed.