I am guessing those parts are different from my 2003 3/4 ton HD avalanche?It occurs to me that with a non-clamping brake, the ABS will never need to actuate at that corner. AFAIK, the traction control can apply the brakes (and I activated it several times), but I don't know if that's the same action as cutting brake pressure. This doesn't seem like a control module failure, more like a mechanical issue inside the "pump" section. Even junkyard pulls aren't cheap and that swap means inevitable DOT-3 shower, then hours of bleeding, but that may be where this is headed.
I am parting it in case you can use any of it.
It's a clean California truck