Hearing Derik's reply the three elders frowned but did not make a move. They heard all the conversations and they have seen everything that has happened. Derik may be the death god who invaded this world and gave them a chance to return to the central continent but that's just it. If this man chose to go against them, they definitely will not hold back against him!
In fact, they find it extremely infuriating that a former god whose power has been reduced to this level dares to go around making bold claims! If they don't deal with him now, it will be harder to do that in the future.