Tommy asks Johnny "Who beat me in the finals?" insinuating that he was the runner-up in 1983 after beating Vidal. However, in the original movie, it was said that Bobby Brown was last year's runner-up.
When the old Cobra Kai gang were together at the bar, Bobby mentions the "no mercy" stuff taking place after high school. They were all still in high school when Kreese snapped after the All Valley Karate Tournament in the first movie, and all left the dojo afterwards. Bobby would've likely been the first to leave (as he always had drawn a line as to how far he would go, unlike the others), followed by the rest.
However, the events of the first movie took place during the gang's senior year of high school. The tournament was in December, which gave them roughly six months before they would finish the school year, graduate, and go into the world. They would still likely have the 'no mercy' mindset that soon after quitting Cobra Kai, so it would be a difficult transition for them. Jimmy even mentions that Johnny got the worst of it, and it's revealed that Dutch was doing time. This all stems from the Cobra Kai mentality, so Bobby's comments make sense.
At time index 1:06 there are spray painted planks of wood on the fence that do not match the rest of the fence. These are new lumber, whereas the rest of the fence is weathered. This is so the spray painted ones can be removed and replaced later with the original planks so that the fence will retain its original look and maintain its continuity.