[gtsteve]

1k sounds like a discretionary amount that would quite neatly fit within a manager's budget for external consultants and so on, which is probably what they'll say you are when accounting for it. They're trying to fly under the radar, and have likely kept this knowledge to only a few people.

The organisation will never change their ways unless they get bad publicity or have to spend so much money that their c-suite gets involved.

I would be wary of trying to negotiate the payment upwards in case you are accused of extortion; just explain you'll disclose publicly in 30 days, which is more than enough time to fix what I assume is a web app backend bug. You don't want them dealing with this kind of issue as a feature to be implemented when there's space in one of the future sprints.

They may try at this point to negotiate the payment upwards, which is a matter for you and your conscience, but I would say that if you don't get something close to 100k, it's likely to be swept under the rug internally and they'll never learn from their mistakes.