RIMURU'S BIG FOUR EXPLAINED IN TENSURA! | TENSEI SHITARA SLIME DATTA KEN (SPOILERS) 

Definitely!! I have a lot more

@@GreedSekai where are you from brother?

thanks

At that time Zegion had not yet joined the executives, but agree that Veldora definitely should be there lol

Veldora already has an assigned job during the festival, he's the food vendor manager haha. After the festival he "Works" as the end Boss of the Labynth, allowing him to not be forced to suppress his Magicules and lay around being the lazy Otaku-Dragon he is haha. Rimuru essentially made him Ramiris' problem. Rimuru is great at shifting such responsibilities onto others haha.

and it would be understandable, since Gobta was once said to be one of the best hobgoblins, although he maintains his Goblin appearance

At that time he had not yet joined the executives, being only the guardian of the Trents

​@@GreedSekai Yeah, he was around but not in his evolved state yet. As you said, he is currently assigned as the guardian of the Dryad's Trees. He appeared in Slime Diaries, he is the large Beetle that was injured but saved by Rimuru. Rimuru reinforced his damaged Carapace with part of his own Slime body woven with Sticky Steel Threads. Veldora eventually trains him to be a warrior, which in turn forces his evolution into his nigh unstoppable humanoid form. He is an absolute beast.