Vayne Condemn not granting assist [Gameplay]

I don't have a video or picture of it happening and I don't want to spend my time recreating it but here's what happened.

I was a vayne in bot lane with my trusty support and the enemy jungler ganked us. My supp and I were backtracking to the safety of our tower right when the kahzix (enemy jungler) jumped at me. I condemned the kahzix TOWARDS my tower but he did not contact the tower. He suffered a couple of shots and my support was able to clean him up AFTER he killed me. But for my condemn I was not granted an assist. I don't believe I attacked the khaz at any other point in the skirmish. No assist and no gold, how's a girl supposed to buy her boots with no gold?