I just had a courtesy car last week although they did show me around they never marked down any scuff or condition, so just in case I took 4 photos, front/back/sides all straight on. When I returned the vehicle they never even came out to check.
James you’ve done the right thing by informing the hire company, if your able to, to ease the worry and if you’ve got the car for a while it may be best to take photos at this point, if your unable to or the hire company is close by you could always pop in and get them to up date the form to your satisfaction.
to be honest upon your returning the car they will probably take little notice, and by informing them you’ve covered yourself.