Set them free. At least for now

The more you analyzed the situation the more obvious it became that you achieve nothing but doing what your father did. Execution of that warrioress will bring nothing good for your tribe. And it will provoke the war with that amazon tribe that arrived recently. War that will give you nothing but unnecessary causality and very modest loot. Even if you chose to get breeding slaves, amazons are the worst candidates for that role, slaves that know how to fight destroyed nations far more powerful than your tribe. What is more important, those female humans are very handy to have nearby because they are hostile not only to orcs but to other human groups... Old strategic axiom says that enemy of your enemy is your friend, something your father failed to understand

"So" You say breaking minutes long silence that you used to think the things over "I think our little conversation is about to end " You unsheathet your knife, smiled to her fear and then cut her ropes free " You will get your weapons back and will be escorted out of our territory. I want you to tell to whomever is your leader, that my clan has no intention to wage war with you. Treat that as my official offer of mutual neutrality. Should your ruler decide to discuss other matters, I am waiting for her or her official envoy any time. Did you understand, Sheila?"

She nods "Yes." then pauses and adds " You are very strange goblin, Vehumet. Can I go now?"

You gave all the necessary orders and the amazon was escorted out of the camp, leaving you to care about other problems of the tribe. Two days later one of your guards informed you that envoy has arrived. It was Sheila again, but you required some time to recognize her. This time she wears a comfortable but still elegant white dress, had a diadem on her head and her lips painted in red using some flower "Greetings Chief Vehumet. I am Sheila, Daughter of Ramia, my mother sent me as an ambassador to discuss our peaceful coexistence"