The intent in forbidding harnesses was to prevent an ARC-AGI specific harness, which for example presented the game interface in a more agent-friendly way.

What NVIDIA has here is a generic "evolution" harness, which can be used for any problem.

I think it would be fair game to allow OpenClaw, Hermes, Codex, Grok Bot, this NVIDIA thing, to compete, as long as they don't have ARC-AGI specific skills, toolset.