I need to bend the flat cut piece along the curve. What is the best way to achieve that?
There is one more approach to make the part. Instead of using sheet metal, use standard ipt file , extrude the desired shape and then use the shell command at last to make it hollow.
Go to 3D Model menu
Within Modify tab find Bend Part button
Select Bend Line on Your sketch
Set Bend Radius equal to Curve Radius and with the Side and Direction arrows change right bending side and direction.