My understanding so far is that that Mythos (and any model in general) can produce candidate reasoning but you really need a system around that reasoning that is capable of producing auditable security findings.

So, success is coming not just from the model but also from the harnesses they built around it. The Cloudflare post was more detailed on that front and I wish the rest would share more about it.

The Cisco spec is interesting too, it pretty much describes an architecture of a harness: https://github.com/CiscoDevNet/foundry-security-spec