Zhu Bufan had thought about just making up some random excuse to fob Long Na off.
But he couldn't bring himself to do it, knowing full well he was using her and then lying to her about it, which would only add to his unease. But to tell her the real reason, Zhu Bufan couldn't manage that either and didn't dare to say it.
So he left things ambiguous, which was for the best for both parties. If Long Na trusted him, she would help him. If not, he wouldn't force her.
"I'll help you!" Long Na struggled for a while before replying.
"Thank you!"
...
After leaving the restaurant, Zhu Bufan went straight back to the Sheraton Hotel.
As for the matter of Long Na's father, Zhu Bufan was confident; he believed that Long Na would certainly help him, since, after all, that girl fancies him.
So now, all Zhu Bufan had to do was wait.
And since it was a matter of waiting, Zhu Bufan made the direct choice to return to where he was staying.