This was my original workup to post. I thought it was way too busy, so I culled each horse to one line.
I believe your paceline is in that bunch.
My observation was that 8 Hi Ho was a stretch runner the kind to "avoid like the plague" according to advice from the matchers forum. Most of the color is in the final fraction. And he did run the stretch today, only from the front of the pack instead of behind. That's why nobody caught him. Generally, you want to see that a horse will run closer to slower instead of keeping the same distance from the lead in every single race.
Add that to the tandem loss to the 7 when they both ran sustained and you have a single bet on the 7.
In retrospect, this would have been a really good race to take on a two horse bet.