Good news! First of all, thanks to by96 for the good talk we had earlier today.
I got it working by adding a simple HDMI 4K@60hz switch (wasn't using it) between the Strato K and the Trinnov Altitude.
View attachment 12215
Since it was working prior to last week, I still maintain that either Trinnov broke the HDMI handshake between this device and the Strato K for 4:4:4 content or Kaleidescape broke it with the latest update. Coincidentally, they both had updates last week. I'm sure it would be one blaming the other if I brought it up to them.