Your metal came today.
First picture (I assume shows the bend near the edge) sight down the top edge and you can see it deviate.
The second picture show the bend center front:
Here is the part after the English wheel. The location of where the bend had been is in the front.
Here is a view of the top, the location would still be in the front left.
I did try the new material. I obtained about 1/2" of compound bend with one pass of the wheel. One measurement shows I need about 2".
Do me a favor and measure on the trailer the distance between the rivet holes on the long dimension. I really need to hold the original part as if it was mounted in order to get the same shape.