You are correct.
Dakshinamurthy (one who faces South) is recognised as an avatar of Lord Shiva as Adi Guru (the first Guru) who taught a few...in silence and not in silence, at different times, so it is easy to get confused, and because there is also no definitive answer and it's not something one can simply "look up for reference", people have reached their own conclusions and none of it can be proven either way:
https://www.quora.com/Is-the-story-o...-Sadhguru-true
In some pictures, Dakshinamurthy is seen with four disciples, in some, five...in some seven:
https://goo.gl/images/RTFSRA
I know that Sadguru has it a bit skewed though, even down to the translation of Shiva's name..
However, since this all happened at the start of this current ante deluvian manvantara, some 25,000 years ago, the details are all a bit sketchy..
OR...As my Higher Self just pointed out while I just typed the above...Maybe Dakshinamurthy appears at the start of each manvantara and has different disciples? One time, it was the four Kumaras, another time it was the Seven Sages...
I just go by Tamil legend...However, the Nath tradition says another thing, Sadguru another thing...and nobody knows.
The only thing that is agreed upon is that Dakshinamurthy is the Guru within one's heart, and teaches the student until an Earthly Guru is found.
Aum Namah Shivaya