Hey, I used to handle customer service for one of the UK’s biggest leatherman retailers so have a fair bit of experience of this.
Whitby and Co are exceptionally good, they’ll honour warranty claims on virtually any tool you send back to them and will do blade/tool replacements on any of the full sized tools aside from newer riveted ones. Smaller tools (Juice, squirt) are usually riveted so usually the whole tool usually needs to be replaced.
I’ve sent back a tool to them which was 20 years old and looked like it had been dug up from a swamp. By a JCB. They couldn’t fix it so the bloke got a brand new tool and his old one returned to him, since it had sentimental value.