OP

Quoted from Zitt:

Unclear which issue your asking about.
Stern is taking 25ish days to respond to my tech support emails.
The last message from them indicated that my issue with all the switches reading closed when connecting "1) the first one is if i connect opto board #5 to the switch matrix; it lights 5 or so optos as closed." is a bad transistor on the CPU board.
I haven't been able to confirm as I've asked them for a clear, legible schematic page for those switch matrix transistors.
The phantom warp ramps they last asked if I've tried swamping the "opto board" I assume they are talking about the LM339 board... but they may be talking about the board holding the opto.
These long periods of silence from them is just ... silly. At this rate my machine will be broken until 2024.