The TV signals got better, but I noticed my Zoom 5341 still reported fairly poor signals and the one locked upstream channel reported a upstream signal strength of 51 dbmv.
I removed the coax cable and waited for the modem to lose sync and then reconnected the coax cable. When it locked, the signals looked a lot better and all three upstream channels locked with an upstream power of 47 dbmv.
I can only conclude that once the Zoom 5341 decides that it's lost channel bonding it won't try to re-establish until it completely loses sync. That seems like a fatal flaw in the mode.
In any case, signals are bad during the day and okay at night. Here's the current signals reported by the modem:
Channel Frequency: 651000854 Hz 669000244 Hz 675001465 Hz 680998169 Hz
Modulation: 256 QAM 256 QAM 256 QAM 256 QAM
Signal strength: 2.4982 dBmV 2.2278 dBmV 1.6749 dBmV 0.9289 dBmV
Signal noise ratio: 37.356 dB 37.936 dB 37.356 dB 37.936 dB
Channel Id: 9 7 8
Upstream Frequency: 22000158 Hz 36200258 Hz 29400249 Hz
Upstream bandwidth: 3200000 Hz 6400000 Hz 6400000 Hz
Transmission signal strength: 46.5000 dBmV 47.2500 dBmV 47.5000 dBmV
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