Errr..errr..I don't know about expert, but here are my two cents:
I'd call him a 6w5 for sure. And tbh, I'm leaning ISTJ - but admittedly, that could be due to the situation of they're in. However, I have a hard time believing an INTJ would willingly do a job like that. It's dealing with people an entire day, and it would wear out their inferior FiSe really quickly. It leaves no time for big picture thinking at all. Meanwhile, this guy is focused on the road, rules, safety...the one time he does talk about something else it's to use a mnemonic device that comes from mythology...that looks like inferior Ne to me. Ne associations in the service of Si dom. I also know several STJs who absolutely love driving and are absolute traffic nazis on rules and conduct, which seems to resonate with this guy.
His hammering on the boots (granted, important detail), the mnemonic device and the listing of all the distractions she's so far let them endanger and his pride of the car and being a small business owner all feel very much like detail-oriented stuff, to me, personally.
I'd give her ENFP 7w6, for sure. They can be on the border of that S, more easily, but she seems too spacey and not 'relishing' the Se experience of driving a car as much as I'd think an ESFP would do. Space cadet could very well be her middle name