iPad Pro HDMI output at 4K60 444

Hey there,

I'm currently using an iPad Pro 12.9 4th Gen and I'm trying to capture the display with a few capture cards (Elgato 4K60 Pro MK.2, Magewell Pro Capture Dual HDMI 4K Plus LT) via various USB-C to HDMI adapters. No matter what I do the output signal is 4K60 420, so it's outputting a partial color space, because of this I'm getting weird flickering and checkerboarding in the capture footage via either capture card.

My assumption is that 4K60 420 is simply a limitation of the iPad Pro 4th Gen, I'm wondering if the new iPad Pro with the thunderbolt connection and the M1 can output at 4K60 444.

Seems like a highly technical question that will be difficult for people to answer, but I'm holding out hope that someone knows something.