Damn, looks awesome. What about a remote DIY AC chiller? Take a 5000 btu window ac and use its coil to chill a glycol resevoir. One loop goes to the palate keezer. Its more cooling than you need so the excess capacity could be zoned to other ferm/ lagering chambers. Get more palates and you can skin it all the same.
Here is an example buildbut you could just use an eBay controller for each zone instead of fermtroller.
Don't think of it as a keezer dieing but an excuse to eventually get a conical.
I was talking to my neighbor last night, who was following the build and was very impressed. His Uncle repairs freezers and refrigerators. So he's going to give him a call to see if there's anything we can do.