I work with the fish shockers in Dinosaur. There are lots of big trout through Lodore Canyon, but they end abruptly at the Yampa confluence. If the water is clear, you should be able to catch some. Jones Hole is good as always. We've been seeing a few trout through Whirlpool Canyon in the riffles, probably due to the clear water from lack of storms and flash flooding.
The pikeminnow is a nice one! But please make the release quick and don't take too long with the trophy shot on shore. That fish could be older than you. It's definitely 7+ years old.