mistake for

I mistook that person for a staff member.

私はその人を従業員だと勘違いしました

I mistook that person for a staff member yesterday.

私は昨日その人を従業員だと勘違いしました

I mistook that person for a staff member yesterday because I was tired.

私は昨日疲れていてその人を従業員だと勘違いしました

I mistook that person for a staff member in the hotel lobby yesterday because I was tired.

私は昨日疲れていてホテルのロビーでその人を従業員だと勘違いしました

I mistook that person for a staff member from a distance in the hotel lobby yesterday because I was tired.

私は昨日疲れていてホテルのロビーでその人を遠くから見て従業員だと勘違いしました