bentm

You are correct, nylon doesn't take dye well if at all. Because it's a synthetic/man-made material, it's also non-porous. Pigment is introduced during the fiber process of manufacture. Any synthetic is a challenge to permeate, but easy to melt & without a fire-resist finish is highly flammable/melts quick. Many synthetics, and some organic materials with a finish on them, will assume a permanent shine when ironed or exposed to temperature extremes.
A burn test using a sm. sample can be used to identify its fibers' composition. If a fabric or thread is synthetic, when flame is introduced momentarily, the result will stink; the caulderized edge will stop unravelling & become rigid & brittle (no ash.)
I tried to dye a tux black once with a polyester collar. I thought maybe if I heated the water solution enough it would soften the poly. & absorb said color. By rule, the hotter the dye bath the better. I achieved only a slight grey.
My roommate gave me any idea, however. He has a jeep, and recommended jeep wax to my client as a preventative care measure. Ask a Jeep fanatic for a preferred brand, I'd tell you but mine's asleep.) I know he recommended applying it twice a year at least (one application just prior to prolonged use (in my clients case, while winterizing the boat.
For a camouflage finish, maybe consider the wax as a sort of paint. Buy the camo colors you want and buff it on. You could use clear wax on top to prevent the transference of the colors or blend them together and soften sharp color transitions.