Analog tuning uses Microsoft's DirectShow API. Frequencies are not really involved. All you need to tune is a channel number. If it requires further tweaking to tune, something is not right with the driver.
To manually enter a Cable channel, select "Cable" from the Type list on "Add Channel" tool. The only other boxes shown would be Name and Channel. Enter a name ("Cable 5" for example) and a channel number (5 for example). If you get "no tuner is available to play this channel" error, check to make sure the tuner is set to Cable, not to Antenna. Your description seems to suggest maybe you had your tuner accidentally set to Antenna.
In the case of Cox Cable, the analog channels 2-6 & 7-13 NTSC, standard frequencies, the same as OTA. So when I test, I test it both ways, because both should work the same. In 18.0.188 neither work.
However, manually I can enter analog channels. If the analog tuner config is set for cable and the analog add-channel sequence is also set for cable, or if both are set to antenna, I get this error
put_CountryCode failed. Cannot setup TVTuner. Code: 0x80070057
But it does receive the channel with audio. However, the frame update is only once per every 5-10 seconds.
If the analog tuner is configured for antenna and the analog add-channel sequence is set up for cable, or the reverse, this error shows
Cannot Run Graph
Unspecified Error
And there is no reception at all.
It looks like the the antenna/cable switch in the tuner config and that in the analog config are controlling the same 'switch' in the tuner which was intended for two RF inputs, an antenna and a cable connection. As long as both the tuner and the analog config in MC are set the same, either cable or antenna will receive channels manually, though somewhat flawed with the low frame rate.
But no combination of settings will receive any channel during a scan. Only manual entry.
--Bill