No, because she doesn't sound "stupid" in the movie. The mountain of evidence against her is so extreme that being able to carve out any narrative in which her innocence has any plausibility requires such a calculated and well constructed plan that is shows a high level of social intelligence and self-control. Fielder literally lives with her 24/7 for weeks and her mask doesn't slip. You don't have to believe her story to recognize she's not a "stupid" person who "does not know when to shut her mouth".