Are salaried employees required to complete a timesheet

That's up to the company. They may be required to report tinme for attendance purposes.

Any employer can require any employee, including salaried, to complete a time sheet. They may want proof of attendance or are just researching where and how their employees devote their time. I work as an administrator in a school district. We all had to fill out time sheets after one administrator was noticed playing golf on a day he had not taken a vacation day.