This was a miscommunication... The Detective was not specific to which two people were supposed to kill each other... But the Detective hoped that one would assume that the Detective was talking to the other two players who were not proven to fight it out... Flaco interpreted it as there only being 3 players left (even though there were 4) and I have to say that if that was the case I don't think the Detective would ask the proven to 1v1 the last player as it is obvious who the last T is...

To answer the question it was RDM and Flaco being slayed was the right thing to do...

However the situation probably could have been avoided by using the names of the players the Detective wanted to have kill each other rather than naming the player "other guy"... Or the players could have asked the Detective to be more specific as to who was supposed to kill who...