In one of the videos, the man in a white shirts and jeans sitting on the steps says “Kak ti?”. This variant is not taught (not at least at level 1) and the expected choice is “Kako si?”.
This is just the urban LJ dialect. They cut the ends off a lot of words and slur things in a predictable yet unintelligible way for an outsider. You might need to know it in the city or to watch movies and TV that are often set in the apartment blocks and suburbs, but everywhere else is going to chop and press the language in an equally strange way or use different idioms altogether. If you want standard Slovene listen to the host of the Joker quiz show, Mario Galunič. He’s a Slovene buff and will often mirror the dialects of contestants on the show for fun.