That code is not accessible to us. The report to NCMEC would be generated by Apple after they have manually reviewed the derived images included in the security vouchers your device submitted after it analysed your photos.
No, the tool that reports to NCMEC is on Apple employee workstations (or a private server). The stuff running in the iPhone essentially just flags things as possibly-CSAM, after which someone at Apple verifies it.
Now, I suppose you could DDoS Apple's verification process.
Either way, though, it's not like anyone who would do either of these things would win any points in the court of popular opinion. I can see the headlines now: "Hackers Disable Apple's CSAM Reporting Tools; Legitimate CSAM Reports Get Lost".
