The code is open sourced

There's no meaningful inspection of LLM code, because the real code is the model weights.

See Sleeper Agents (https://arxiv.org/abs/2401.05566).

Who in their right mind is going to blindly take the code output by a large language model and toss it on a cruise missile? Sleeper agents are trivially circumvented by even a modicum of human oversight.

but what about training data?

The weights and data pipeline are open sourced and described explicitly in the paper they published. The non-reasoning data isn't nearly as interesting as the reasoning data though