Wen Qing bid farewell after refusing the trio's offer to send her back.
Zhuo Erfan's group originally came out to pursue the Zerg scouts. But with those scouts eaten by Wen Qing, their mission was over. They didn't know how to express their gratitude after receiving the set of body refining techniques from Wen Qing, so they wanted to invite her to visit their expeditionary army. But it was obvious that Wen Qing was reluctant to join them, so they had to give up. There would always be an opportunity to repay such a big favor later.
The three men hadn't even made it back to the Expeditionary Force compound when their optical brains were blown up.