It doesn't sound like you did free work for them. It sounds like they subcontracted you and you did free work for someone else. Someone told them to have this done quickly. Maybe they were supposed to have it done already. It doesn't matter.
They submitted your work and sent you the feedback they received.
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It doesn't sound like you did free work for them. It sounds like they subcontracted you and you did free work for someone else. Someone told them to have this done quickly. Maybe they were supposed to have it done already. It doesn't matter.
They submitted your work and sent you the feedback they received.