There should be no way at all for them to identify a bot client, the reason for this is that all the bot client is, is a normal rs client, with all of the bot features. Its this (http://services.runescape.com/m=rswiki/en/RuneScape_Client/Multiple_Configuration_Setup) with the bot features.

apparently this bot client injects information into the rs client,so that could be why.

people use third-party clients to play. they do not have to grounds to ban because your account has logged in with one.

Also, I highly doubt this client can be detected.

I expect some of the movements the scripts cause can, so taking necessary precautions will keep your account safe.