If you really want to remove the odor completely, you need to find the exact Source/s of the odor...
If there were mothballs in the car, where exactly were they ???
I have been able to successfully remove other Detailer (?) induced odors, cover up odors, etc., by first if possible finding the source of where it started, , removing that odor there or all the places, and then completely steaming and extracting the entire vehicle to remove the Other Odor, that the idiot was too lazy to remove, and just took the easy way out..
For example, I got a 2003 BMW M5 that had an odor that made the new owner so Sick, he drove it home and parked it for over a year in his garage; he could not deal with the cover up smell..
I found the strongest part of the car where the stupid bomb was placed, really steamed, extracted a few times, and then went over the entire vehicle, every square inch, and removed the original Odor, Nicotine, from every square inch of the car..
I was removing brown nicotine as seen on my white towels, from the entire car, worse on the driver side, driver side glass, sun shade, headliner, and followed a brown nicotine trail all the way to the driver side back seat areas where again, a lot of brown stuff came off of the headliner and the inside back glass..
Once it was done, there was nothing but a clean smell, no added smells, and the owner was ecstatic..
What we all need to know is that some odors are really bad for some people and anytime you try to cover up the original source of the odor to begin with, you are just compounding the problem and not really getting the source of the odor out.. And the Client will not be happy and this odor may have a health issue for him and his family later..
Good luck with this,
Dan F