XPS 9310 not supporting 4K through USB-C dock

Hi,

I'm having trouble getting my XPS 9310 i5 to display 4K with my USB-C dock. It's an HP G5 USB-C dock that is plugged in via display port to a Samsung 4K display, and an ASUS 1920x1200 display. When plugged in, the XPS only supports 1440p on the 4K display.

However, when I plug in my work laptop (which is an HP 10th gen i7) into the dock, it supports 4K/60 on the Samsung display.

I've got all the latest BIOS updates and drivers (as of January 22, 2022) on my 9310. I can't seem to figure this one out. Any ideas?

Thanks.