Thanks to being directly teleported from the boundary of the Fifth and Sixth Heavens to the hinterland of the Sixth Heaven via Nalan Mingxue's formation disc beforehand, Li Jing and Ye Piaoran reached the entrance to the little world leading to the Seventh Heaven in only five days.
Li Jing did not deliberately erase the memories of Wu Zongyi and Nalan Mingxue.
He'd already "blatantly robbed" them once, so there was no need to worry about his reputation anymore.
What's that saying again?
In for a penny, in for a pound.
He had already done it once.
So, let's be straightforward!
Moreover, having visited the Haoran Righteous Qi Palace, the impact couldn't be wiped out by just erasing Wu Zongyi and Nalan Mingxue's related memories.
Those in higher echelons of the Haoran Righteous Qi Palace who knew about it wouldn't be too many but also not too few.
It would be too much trouble to find each one of them and "brainwash" them...
It's clear.