I just looked that color code up for 056 basecoat , I own a body shop and we mix Onyx water based basecoat made by BASF, there is an updated color mix on it, which means someone actually sent a piece of that color car to the BASF paint lab and they made a mix that actually matched.
I have run into bad color match on some new 16 model Subarus, which makes it a pain to tint, cause they are new fancy metallic colors.
Looks like your bumper just needs a little extra yellow or gold in the mix.
056 has to be clear coated or the bumper would only have the base coat color on it and would look dull. Clearcoat has been used on all factory painted vehicles since the Late 80s early 90s