While the Camallanus still appear well (there are still red worms hanging out of most of the Macropodus), one of the male Macropodus died. Was it worm-related, meds-related or just coincidence? I'm inclined to think it's something other than coincidence. After all, the only visibly infected fish are the Macropodus, so I'm guessing that they are more susceptible to the Camallanus.
It makes me wonder whether there's a stress component. The Macropodus are likely to be the most stressed fish in the tank, since their struggles for dominance consume a lot of their energy. Interesting thought.