Is “In the Romance, Guo Si first appears leading a large force to besiege and kill Yuan Wei, while the official history, through the mouth of another, mentions that he fought with few against many.” true?

In Chapter 5 of the Romance of the Three Kingdoms, it is written that he led a large force: "On the road, Li Jue and Guo Si were first ordered to lead fifty thousand troops to guard the Sishui Pass." In the Records of the Three Kingdoms, Book of Shu, Biography of the Former Lord, it is said through another's mouth that his troops were very few: "Cheng said to Fu: 'Guo has several hundred soldiers, yet he defeated Li Jue's tens of thousands. It is only that you and I are not of the same mind!'"