Upon further reading, I discovered that MATLAB restricts the number of workers in `parpool` to be equal to the number of physical CPU cores when working with the Cloud Center. Therefore, one cannot utlize all vCPUs.
Specifically, MATLAB's documentation states: "Cloud Center supports at most one worker per physical core. Although Amazon Web Services machines can have many virtual cores, Cloud Center restricts use to at most one worker per physical core for optimal performance."
