Hold on episodes are done by different directors? I thought Tabata was working on them
Tabata hasn't directed any of the post launch XV content and instead is producer on them, he's been busy with his new IP.
Kenichi Shida was director of Episode Gladio and Episode Prompto. Kenichi Shida was Game Section Design Manager on the main game.
Tohya was co-director on Episode Prompto, I couldn't find anyone named "Tohya" in the main game credits but there was someone named "Tsukasa Toya" that was out of four people who are credited for "Battle: Niflheim", so I think it may be a romanization error on the "Tohya/Toya" part, and he was probably on it because of his involvement in creating Niflheim enemy content.
Takatsugu Nakazawa was Director for the free update content and I believe he was also director for the Royal Pack DLC. He was Battle Director and RPG System Planner/System Designer on the main game, he was also a battle planner on FF7, FF8, FF10 and battle director on FF10-2.
Kazuya Takahashi Directed Comrades and he was part of the "Quest" team on the main game, also credited on FF9, FF10 and FF14ARR for various artwork roles.
Takefumi Terada who directed Episode Ignis and is directing Episode Ardyn was one of many credited as involved in "Boss Battles" on the main game and he was also an event planner on Crisis Core.