Are you sure it was cut and isnt the Toe bar diffuser? there is 2 versions of the diffuser, one for with a toe bar(has a square cut out to accomodate the toe bar) and one for without.
Am definitely sure it's not the one with the cut out as I have seen them online. Mine has been cut with a hack saw up to the honeycomb bit and it looks nasty if you look closely! For some reason my bike rack constantly grounds when am pulling out of petrol stations so I don't think it's the correct tow bar for the car.
I like the idea of a removable one so I can take it off when not needed plus the car looks better. I don't suppose any of you guys know where I can order a rear valance with the tow bar cut out? cheers