OP wonders if there’s a version of the Thinkpad keyboard with a metal case.
The Tex Kodachi has the Thinkpad layout in an aluminum case, but it’s unfortunately out of stock on the manufacturer’s website:
https://tex.com.tw/collections/keyboard/products/kodachi
The Tex Shinobi isn’t metal, so no help there, but it might have a little more rigidity and still has that Thinkpad layout: