Can't get my hackintosh to boot with an addition of a new NVME SSD

Hi - I'm quite stuck here.

I've been running my hackintosh without any problems for about a year.

I bought an extra PCI-e nvme SSD for my workstation storage purposes. The Hackintosh doesn't boot when I plug it in displaying this error.

When I unplug the SSD, everything boots perfectly off my primary m.2 SSD.

The new PCI-e SSD doesn't appear in my bios settings at all.

I briefly fixed the issue by changing the position of the m.2 on my motherboard. The PC booted into MacOS without any problems and I was able to see the PCIe drive. I formatted it (during the windows installer) whilst trying to install windows, but then decided against installing the OS due to complications.

However, since then, the problem came back and has stayed ever since.

I'm out of ideas and it seems that this is yet a fairly unexplored issue on the web.

Any ideas / solutions would be greatly appreciated. Thank you!

Hackintosh SSD (working SSD)

PCI-e SSD (causing trouble SSD)