If you think about the bigger picture, it's actually a reasonably impressive achievement from this author: Gu clan sent Xun Er to dig around in the Xiao clan to find the ancient key. They could do it because of the ancient connection with the Xiao family. The Soul Palace noticed the Na Lan family has a daughter in an arranged marriage setting to the Xiao clan, so they had their subordinate Yun Lan sect recruit that daughter, Na Lan Yan Ran, to be an important figure in the Yun Lan sect. That's how they could infiltrate the Xiao clan as well. However, the marriage fell through due to Yan Ran's personality, so the Soul Palace had to come up with something else.
It was suggested Xiao Yan's old man, the clan patriarch, might have been kidnapped by the Soul Palace already, but seeing how the Soul Palace is now causing more trouble, it's obvious they didn't get what they wanted. That's natural, of course, since we know Xiao Yan is actually carrying the ancient key.