If they break the attestation, they would do it for something of value. Inference is much lower value than for example secure communications providers making use of the tech. It's extremely difficult to keep this secret. Breaking attestation is extremely valuable, by running an AI provider as a front and exploiting their own infrastructure, they would get access to what is mostly porn role playing and retarded chat. Wasting such an exploit would be stupid. I'm not saying they are not stupid, but it's very unlikely they would waste an exploit on this.