Google doesn’t have a program for that, and they’ve already said accidental damage isn’t covered by warranty.
So if you crack your screen, it’s entirely on you to just buy a full new one. You could turn it in for recycling, sure. But that wouldnt go be be refurbished. Most companies don’t do their own refurbishment, and the pixel watch does not any parts available to it outside of manufacture.
Personally I have an A54, so I'm not entirely sure but the last thing I read is that the watch is fine you just lose out on a couple of items (due to the Galaxy Store not being on other devices).
Here are some Galaxy Watch features that require a Samsung phone: