In case anyone ever happens across this with the same issue, here is the issue I found out a year ago:

The computer that is being utilized has a BlackMagic Decklink Duo 2 Mini installed into one of the expansion slots on the motherboard. All four SDI camera inputs are plugged into that and is then sent to the CPU. The problem was that the Duo 2 Mini was installed on a x4 lane slot and so was being throttled. It needs x16 to the CPU for it to work to its full capacity. At 1080p60 with 4 different SDI feeds being sent at the same time, the computer sacrificed clean audio to ensure consistent video quality due to the throttling that was taken place. Unfortunately that motherboard that was installed only had one x16 slot which is being used for the GPU. The company that had sent the computer for broadcast purposes had accidentally installed the wrong motherboard so I was able to upgrade it bringing it to the proper specs and once tested again, all issues were immediately resolved.

My memory on this is foggy so I might be incorrect on the minimum lanes required to not experience any issues with the Duo 2 Mini being inserted, it might work with a x8 lane slot but you would have to test that out and verify.

I am by no means an expert on the topic so take everything I say with a grain of salt but this is what I discovered and what eventually led to its resolution.