The errored state seems to have been an unrelated issue. I restarted the container and then restarted those torrents and they were able to download without issue. Moving them all into the container at /tmp didn't make a difference except maybe with transfer speed because of the kind of drive it was using. I moved everything back to where it was and I am getting good download speeds.
I'm not sure which change made the difference, but the completed torrent that I am seeding is now uploading very slowly, less than 50 KiB/s. The other two still show zero.
I can check my router's bandwidth monitor to this device. When the torrents are paused there is zero activity in either direction. When they resume the bandwidth monitor reports about 10-100x the transmission in both directions than the torrent client does. 5-10 Mb/s upload instead of 50 KiB/s. 300 Mb/s download instead of 30 Mib/s. This seems like a whole lot for protocol or encryption overhead. Any idea why this might be?