So my setup reverted back to flickering within a few days of my last post. I did some investigating and figured out that the power draw from the 115 LEDs could reach 50W alone, without considering the Pi's draw. I upgraded my 5V 10A 50W power supply to a 5V 15A 75W power supply and I haven't had any flickering since. The live video screen within Hyperion also works flawlessly now, whereas before I was just seeing a scrambled screen.
What's interesting is that Hyperion suggests that the max power consumption is 7.5A which should be 37.5W. Based on that, my original power supply should've been enough but I guess not. Anyways, hope this helps others.