LG 5k/2k no signal with VESA certified Silkland DP 2.1 cable when using HDR

Looking for any input from anyone who has a fix. I received my Silkland UBHR 20 80gbps VESA certified 2.1 DP cable today. Just tried it and enabled HDR. Immediately lost signal. HDMI still works.

I'm on a 5080.

Anyone found any fixes? Know of any response from LG?