Each version of Studio One [ version 1, version 2, version 3 ] each came with their own specific content and or bundled 3rd party software that even the Studio One Artist version would/could utilize.
Studio One v2 came with an Native Instruments Bundle, which did include Kontact 5. The version and name of the Bundle was updated by NI. One was called Komplete Players and then it was later called Komplete Elements. Eventually, NI made some additional updates and the software was no longer available from within Studio One 2. However, all was not lost... as NI placed this collective plugin on their website for free.
- now this was not included with Version 3 when it was released
However, what the Sales person may have mistake your question for is a feature of Studio One 3 Profession; which allows the software to use audio libraries from Kontakt.
This is visible here on the Studio One 3 Version - Feature Chart:
Now if you would like to know were to get the NI Kontakt and several other Plugins for free just go here:
This is a collective Bundle called Komplete Players and includes:
- Kontakt 5 Player
- Reaktor 5 Player
- Guitar Rig 5
- and included Factory content for each