From your description it sound like they want you to sew the strip to the ends of the triangles stopping 1/4 inch from the edges for the seam allowance. Then you would sew the sides of the triangle together to form the hexagon?
I would also sew the triangles into the hexagon shape first and then use the 5 inch strip to connect the 2 hexagons. With careful pinning, you can sew the strip to the 2 hexagons and you will be able to turn it through the end seam in the 5 inch strip, stuff and then hand sew the 5 inch strip end seam last.