In many cases, our basic understand of human psychology and intrinsic motivational factors is flawed (there are several articles and talks about how basic assumptions such as "higher salary implies higher productivity" aren't correct).

Either way, the whole point of the philosophical zombie thought experiment is that, unfortunately, reality/truth itself can be shown to not matter when analyzing human behavior, because the zombie would behave identically as the "normal" human, even though the realities/truths are quite different (the normal human experiences qualia while the p-zed does not).