Most importantly, the other party didn't hold the same advantages that he did, and he couldn't run around every single ship as he did. Zhao Fei couldn't possibly run to Traversing Moon Palace's ship and probe into his background.
It was of no importance whether he was telling the truth or not. His little white lie was all for the greater good. Right now, the most important thing would be to gather up those who held no advantage. As long as everyone could stick together and fight against the tides of fate, so what if his lie was exposed? Miao Yi believed everyone would only feel thankful for him then; no one would hold a grudge against him. Once the group took form, it wouldn't be so easy to split up the people who decided to join forces. Everyone knew it was much more dangerous to be on their own.