This post is hilarious reading. 10/10 would watch the movie.
I second this...
OP, I'm making my first post just to point out how ridiculous this whole thing is. I agree with you that it is a bummer that something fairly simple, like a post collar was botched. Where I think this gets ridiculous is that you seemingly think that the moral high ground is worth the time, emotion, shipping logistics, making this post, among other things. Not to mention you probably initially purchased the frame with a "budget" in mind, albeit Winspace may be a premium brand in the east(china) it is still a budget brand in the west...
The collar from Winspace broke, after 2 years, even if you swear that you always use a torque wrench, no higher than 5nm, is the wrench calibrated? Do you think a collar on a mid range Specialized hybrid or $4500 Trek road bike (not ISM design) doesn't fail under similar conditions? I'm guessing the collar was fatigued, bummer indeed but so is your attitude. Go buy something that's CNC'd from Wolftooth, Hope, i9 whatever from an LBS, they must have some hideous anodized collar for you. Please tell them this heartfelt tale of how you were wronged too by the way, I'm sure they will have a ton of sympathy. Maybe they'll give you one for free to get you to leave quicker.
Snide comments aside, as someone who spent 10+ years at a bikeshop and is now at a manufacturer, you seem like the sort of customer most folks come to dread. The validation you seem to be seeking here, is almost as insane as you demanding a company in China ships you a new seatpost collar.