Except Joe wasn't really the problem, it was Log Trap, plain and simple. While Dieminion isn't exactly the pinnacle of Joe play, he's very solid with him and gives a good baseline as to what to expect at least defensively and he can rushdown so this shouldn't have caught anyone by surprise.
And Kusoru's gameplan was lampshaded by god damn near everyone, it was predictable. Throw V-Rangs, Triple Jump, H Red Hot Kick + Log Trap. Repeat until a solid hit is landed into combo. He literally did not change his gameplan until either he landed a solid enough hit to combo, or Joe died. He also showed that if Raccoon dies, his team can fall apart EXTREMELY fast. Yet very few actually did jack shit about it, hell I think Yipes was the only one smart enough to snap him in. Hell the only reason Rog even got one of his games was because Kusoru tagged Raccoon in for him by mistake.
And for the LIFE of me I cannot fathom why in the world Rog decided to go with Felicia. His Felicia is mediocre at best. If you're going to pick someone for their Dark Mode, you go to the King of Derp, Dark Wesker. At the highest levels of play for each character, I think Felicia can definitely outpace Wesker, but his Felicia wasn't shit, so why not go to a character you barely have to know to win with?
In the end his team was ATROCIOUSLY built, I mean really Spencer/Wolvie/Felicia? It's basically a team of three loners, which made Kusoru's strategy a lot more effective than it had to be.
As yeah you can't learn every team matchup, but there's no excuse for not at least knowing what a character can do on a certain level, which I guarantee Kusoru had in the end. PR Rog couldn't handle that his knowledge and his team was shit, and he decided to be a bitch about it.