Ok, mythbuntu definitely is missing the channel 9 transport streams. I found the following info
And manually added the info for channel nine, as best as I was able to decipher the parameters. I scanned again, and it found channel 9.
# T freq bw fec_hi fec_lo mod transmission-mode guard-interval hierarchy
T 226500000 7MHz 3/4 NONE QAM64 8k 1/16 NONE
T 177500000 7MHz 2/3 NONE QAM64 8k 1/8 NONE
T 191625000 7MHz 3/4 NONE QAM64 8k 1/16 NONE
T 219500000 7MHz 3/4 NONE QAM64 8k 1/16 NONE
T 585625000 7MHz 2/3 NONE QAM64 8k 1/8 NONE
So, maybe it got left out of the config in Mythbuntu and can be added next time?