I found some problems with the escalation contract 251 The O'Leary Conflagration. When I threw the target into the incinerator and ignited it, the game showed that the mission failed. Maybe, there are some problems with the kill conditions you set.
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If it doesn't work, it might be a bug from the game itself (or maybe it just doesn't like saving for escalations). Try to restart the mission et do it without saving. I didn't touch the objectives from original escalations, just the gamechangers so I don't think it s because of me. Restart it and let me know