In terms of credibility, this is the same group / private company that claimed the ramject rotating detonation engine last year. They're the only private PRC aerospace company that works on hypersonic technology, they've been around for 10+ years, have national little giant designation, IIRC the founder was chief designer at CALT/CASC, most of the R&D teams seems seasoned. That said I cannot tell if they're PRC's very budget Anduril, their PR is pretty flash (at least relative to PRC standards) but they have a lot of ambitious vapor ware tier projects / announcements in prior years. It doesn't seem like they ever really had the $$$ to do anything grandiose, but they got like 200m rmb in investment right before YKJ-1000 announcement... Considering PRC acquisition of 1m drones + 1m loitering munitions, maybe sign pivot to budget hypersonic viable business model than commercial space.

Other related relevant info, there was interview according (allegedly) to source within company the the 100k USD / 700k rmb unit price is apparently calculated by outsiders, so it is not reliable. But the more interesting tidbit is the goal of "manufacturing rockets like manufacturing cars" is to drive down costs of missiles to 1/10th price of "traditional" costs, with cited costs of "often in 10s of millions" of rmb per unit. Often as in not always, hinting lower end, i.e. 10-40 million rmb, and I assume in same S/IRBM tier, suggesting those tier missiles are currently in 1m-5m usd range. Likely not higher, i.e. 50-100 rmb range, otherwise linguistically, language would round unit up to 100m (亿).