Xia Peifeng followed up after charging Chu Ling with plagiarism.
Firstly, he posted his copyright certificate on social media.
They were registered in his hometown. Since he was from a small town, Hu Lai was unable to find them when she first verified whether the songs were original. Hence, Hu Lai and Chu Ling felt it was safe to use those songs.
Secondly, Xia Peifeng posted videos of him humming these songs on his secondary social media account.
After he wrote the pieces, he did not release them right away in an album, but he wanted to share them with the public, so he hummed them on his secondary social media account without showing his face.
Since very few people knew about his secondary account, the videos did not get a lot of attention and only a minority of people had heard it.
Everyone could see that the videos were posted way before "Ultimate Singer-Songwriter" was even aired.