When Miguel is trying to convince Johnny to let Aisha join Cobra Kai, he tells Johnny that her father is Isiah Robinson, a Hall of Fame lineman for the Chargers. However, no such Hall of Fame football player exists. The closest match is Isiah Robertson, who was a 6 time Pro Bowl linebacker in the 70s for the Los Angeles Rams and Buffalo Bills. Robertson was killed in a limo accident in December 2018, roughly 6 months after the release of the first season.
Johnny opened Cobra Kai under the belief that Kreese was deceased. In The Karate Kid Part III (1989) it was established that the dojo was a subsidiary of Terry's company. Therefore Johnny would not have been permitted to use the name without Terry's permission.