EAS tries to accommodate a patient’s request to a specific hospital, even in cases when the request is to a facility other than the closest ER.  Of course, there are exceptions.  Patients will be transported to a facility (other than the patient’s request) based on several other factors:
Need for Specialty Center, like a trauma center (critical injuries), stroke center, or STEMI receiving facility (heart attack)
If patient requests a facility that is on ED diversion due to saturation (overcrowding)
If the patient is in extremis, like an uncontrolled airway or uncontrolled bleeding, they are always transported to the closest hospital emergency department (ED)