My Basenji/ACD mix got skunked last year; it was fairly mild fortunately! I think she was far enough away, and there was a strong wind that evening so I think she may have been upwind from the blast.
Anyway, I used the peroxide formula and it cut the odor by about 75%. I waited two days and bathed her again with it, which pretty much brought her back to being "generally suitable for household companionship" LOL. She still had a slight "funk" if I actually stuck my nose in her fur and sniffed, but it faded within about a month.
The odor will fade on it's own (may speed up a bit with grooming sprays, etc) but it will take quite a while…probably a month or more. If you want to speed up the process, he needs a bath. If it were my dog, I'd bite the bullet, get a cloth muzzle & a friend to help me hold the dog, and I'd bathe him with the peroxide solution. If you have help & you get your ingredients, towels, cups for rinsing, etc...set up beforehand (you have to mix the peroxide solution immediately before applying it to the dog) the bath only takes a few minutes. Rub it in & let it soak for a couple minutes, rinse, dry- and give the water-traumatized Basenji a treat afterwards LOL. Might be unpleasant for him but IMO it'd be worth a few minutes of "water torture" to not have to smell a skunk-reeking dog for the next month or two
This is Chloe during her de-skunking bath (she usually loves water/baths, but she managed to put on her most pathetic face for me this time)
And this is Chloe afterwards, drying herself on the carpet and getting some drying-off assistance from Jibini: