Well, I suppose rtsp protocol my be not supported by your Smart TV device. I guess your IP Cam has the option to translate using http protocol also, look for it. Generally the video from IP Cam is usual live-stream, so if used codecs and protocols are supported it must work when you add stream's url into My Playlist section.
The same way you write it here, did you try? There may be a problem that your link contain username:password@ authenticatin params, such a kind of authorization has been depricated and may be not supported by your device. But you should try it.