It's confirmed by the new HGZZ film editor. If you watched the Dang MV, there's second bed scene between Yong Qi and Xin Rong where he's on top of her.
I have a feeling his mom probably imprisons him or threatens him with suicide or something. So YQ gives into the pressure and consummates his marriage with Xin Rong in order to reunite with XYZ in Yunnan. I also heard that Xin Rong in this version remarries.
I don't blame YQ for this, but QIONG YAO!!!