Yes, I know where Ottawa is
Honestly, the trouble you would save your partner would be minimal to none. He would still need to clear customs, pick up suitcase, hand in his declaration and then work his way out of the airport to meet you (instead of working his way to another gate). 8-10 hours of driving seems like a lot just to avoid having him walk to another gate.
When you are looking at tickets, are you looking at routing straight through to Ottawa or are you playing travel agent and trying to put together an itinerary for him? The reason I ask is because if you get tickets straight through, it is the airline's responsibility if they put the flights too close together and would have to put him on the next flight at no cost. If you set up his itinerary and he misses, it can be complicated and costly.
Unless of course, the real purpose is to be together earlier, well then that's a different discussion.