Thanks for posting this! I have now updated the GitHub with test results for durability and to test PD capability. Have a look if you're considering using this!
It is as easy as 123, just a couple of clicks, and its all explained on the GitHub. However, unless you're committing to a 0.6 mm PCB, I wouldn't really use this on a keyboard, especially a full size one. The board really is not rigid at those sizes at that thickness. Weigh a tradeoffs and use it if it works for you!