This reminds me of the old days of Sears Craftsman tools when they would stand behind any Sears product marked "Craftsman".
My buddy that worked at Sears in the "tool corral" (think 40 years ago) told me that people would buy broken tools at garage sales and flea markets and take them to Sears for free replacement or repair. Sears stuck by their warranty as written at the time, one with no elaborate nation wide registration system to verify original ownership.
They trusted the integrity and the word of the individual that brought in the tool. They replaced plenty of tools, even knowing that the people that brought them in didn't buy them new themselves, and sometimes took the replacement tools and immediately sold them. My buddy work there about 5 years and assured me they got screwed heavily and often.
Seems like ZT has that same old fashioned trust and warranty process. For all of their own reasons they may replace your blade. Doubtful they ever intended for someone to buy a couple of scales from a trashed knife and be able to send it to them expecting new a new, sharp blade with all the parts needed to get the minor pieces supplied into a whole, working knife again.
What a steal for you if they do it. As an employer myself, I can't see how $37 would cover a new blade, new pocket clip, incidental pieces, a tech trained on repair to break it down, clean it, reassemble it, tune it up so there isn't whining about poor customer service, repackage the knife, then ship it ( eating the postage as well).
Doubtful your plan is what ZT had in mind when they set up their warranty policy. If they do it ( for whatever reason they might have) good for them. If word gets out though, there won't be a pawn shop, garage sale, flea market, or auction site that has a ZT product on it as they will all be headed back for repair or replacement " under warranty".
Just like the old Sears days...
Robert