Hey, do you have a worklog on this or another keyboard? It's something I eventually would love to do, especially modding an ergonomic with switches.
Plus i've used the MS ergo 4k for almost 5years? (maybe more idk). The ms4k has a nice layout and the negative slope is pretty awesome.
if this sounds like you then yea your only course is to mod one like i did.
couple of things i'd do different.
use a g15 control board (when i open it up i'll really see) so i can better integrate keys/macros/dislplay
make it tenless in the first place (this would have saved me from wiring up the numpad)
use smaller gauge wires and heatsinks instead of just electrical tape to make it look "nicer".
but it works great, just waiting on ups for the g15 to come in so i can hack it into the modded board.