As was pointed out, /names #channel often doesn't work because most servers set +i on users when they connect. Even for servers that don't do this, many people have 'Invisible mode' set in mIRC options. When you are kicked from a channel you can see the person who kicked you - /msg them. If it's a bot, you might try
/msg bot-nickname help and see if you can obtain the owners nickname. This often helps for eggdrop bots.
For channels with channel services you can look up the information of the channel and find out who the Founder is. Using the /mode #channel b command I gave before will look up other channels bans and therefore, show you if ops have set other bans and what their nicknames are, then
/whois nickname nickname to look up their idle time or if their online.
The error message you described is returned on all servers on all IRC networks if the user isn't online. Whether you have /names for this situation or not is not going to affect whether or not someone is online or not.
To be honest, if you saw in the next
versions.txt, "32.Added /names filling nicklist when kicked feature" you would find people posting saying "Why did you add this back?!" - It's all very well suggesting "Make it an option to switch on/off" but this is not practical for every tiny suggestion. I'm a big fan of customising things, but on/off switches cannot be added for everything, there isn't enough space in the dialog box!
Regards,