Without seeing them it sounds like PUI work, kinda ok but to a budget. Obviously, if the wrinkles are at the stitching, then no amount of padding and leaving in sun is going to smooth it out.
Most of those are sound insulation, with a side effect of some heat insulation. Both is good for an interior, there isn't always much difference between brands that have the tar backing and foil top, but then a layer of thick carpet wadding insulation over it is what really helps with both, along with making the carpet fit. Everyone has their own brand or experience, generally if you get a brand name and a decent price, you are good to go. Even the cheap and nasty no-brand stuff has its place, but it tends to already be messy and exposure to hot floor will happily make it ooze out, but it areas where it's 2-3 sheets deep to add packing, it's fine.
Camel tan is one of those colours that even new, didn't match the panel next to it. The vinyl, the cloth, the plastic, the carpet were all different shades which in a way helped the whole interior match, not just one area that looked wrong. There's a few trim pieces out there that are already molded in colour, some take on an orange hue, and of course there's only one or two Camel tan dyes which is probably matched off an original dash paint colour code.
What specific Camel tan parts are you having dramas with?
