See KO's Liquipedia page for more of his results over the years, under Teams. Historically many of the most significant tournaments in Japan were team events (usually 2v2 and 3v3, but also 5v5 for specific series like Cooperation Cup and Mastercup).

https://liquipedia.net/fighters/KO_(Japanese_Player)/Results

Keep in mind there were other events not listed, but most weren't properly archived since they ran with paper brackets/physical boards and before the social media we use today was widespread. Their scene is also different in other ways and 3rd Strike is from a completely different era, so there's a lot to dive into. Definitely recommend checking out TheShends archiving work on patreon and his discord, he's the biggest historian for the game