New update:
The hub arrived this week and I ran it through some tests.
I used an External USB 3.2 nVME Enclosure with a 2 TB WD Blue SSD in it, and ran speed tests on both windows and mac.
For windows, I compared a native USB 3.1 port vs the SSD behind the hub:


For mac, since I have an M2 MacBook Air, I compared an OEM USB 3.1 hub vs. the custom one Cipulot made for this keyboard:


Overall, the hub seems to be working well, and reaching USB 3.1 speeds, and in the Mac case, outperforming a UGREEN hub off of Amazon.
I'm waiting on revised 2U DynaCap stems that fix a minor issue before posting a sound test of the board in all it's EC-ness.