Ask HN: Could a new public marketplace for zero-day exploits be successful?

I understand that others have tried in the past to launch an "e-bay for exploits" but with limited success. The most well-known example is WabiSabiLabi which in shutting down wrote that "The international group had to stop trading its knowledge after controversy and legal threats surfaced from third parts and competitors." But is this evidence that the model is totally non-viable or do you think there could still be an opportunity for an ethical organization to vet buyers (to comply with international law and avoid selling to non-NATO countries or criminals) and do this responsibly and successfully? Also, if anyone is particularly interested in further exploring this concept, please don't hesitate to contact me directly as well.