Driving employee engagement in the unit/location up to SA level means your employer wants you to manage employees up to the SA level.
Executing and sustaining the initiatives at the BU/Location Level through a systematic approach means you will be responsible for policy-making and execution for the business unit.
Assimilation, Communication & Feedback, Exciting Workplace engagement, Recognition Program, Grievance Handling, and Retention mean you will be responsible for handling grievances, employee retention, collecting employee feedback, communication, engaging employees at the workplace, etc.
They have revealed their expectations from you.
Hope this will clear your doubts.
Regards,
Amar Bir Singh