Ah, this is quite possibly the worst nightmare for dog owners in the world. As humans, we understand that skunks are a no-no and to stay away from them at all costs. Your dog, however, will be curious and it is their natural instinct to investigate. If they do happen to come home with a rancid smell, with their GPS tracker attached, you should get the smell out of both your dog and the unit. Here are a few ways that you can achieve it, at least to an extent. Firstly, you can try a mixture of white vinegar and Dawn dish soap to clean both the pet and the tracker. The smell will not be eliminated right away and you will need to let both your dog and the tracker air out for a few days.
If this does not work for you, try to mix a paste of baking soda (one box), dish soap (one squirt), hydrogen peroxide (one bottle), and vanilla. Find a pair of rubber gloves and saturate them with the paste. From there, apply it to your dog and the tracker and leave it on for around 15 minutes. To finish, thoroughly rinse both of them off (only do this if the tracker is water-resistant or waterproof).