In the lecture, the speaker makes a claim that Chevalie's memoir is indeed reliable and accurate, casting doubt on the main idea made in the passage, which says that Chevalie intentionnally exaggerate the exciteness of the events in the memoir and it was unreliable.
To begin with, the speaker states that Chevalie was actually wealthy, which refutes the viewpoint of the passage that Chevalier could not be rich as he borrowed considerable amount of money from a Swiss Merchant. According to the speaker, in Switherland Chevalie did possessed a large amount wealth. But he needs to convert his asset into cashes and it will take several days. Therefore it is reasonable for him to borrow some money from his friends in order to host parties and gamble before his assests were converted.
Moreover, the speaker suggests that the accuracy of his conversation with the famous writer Voltaire could be confirmed, whereas the author insists that it is impossible for him to remember the exact phrases of the conversation. To convince the audience, the speaker provides the evidence that each night after chatting with Voltaire, Chevalier almost wrote down everything about the contents. Also he refered to this notes when writing the memoir. And this action was supported by some witnesses.
Finally, the author mentions that Chevalie's escape from the prison by climing through the ceiling was not true. He had a number of plitically well-connect friends so that they could offer the jailer a bribe for his escape. However, the speaker views this issue in another angle. She indicates that bribing won't work as many more political powerful prisions cannot get a chance to bribe the jailers. In addition, a government document proves the repairment of the ceiling after his depature, which lend credence to his escaping method.
In sum, further evidence and reasoning logically attack the viewpoints in the passage.