[Matnix]

pawn Код:

public OnPlayerDeath(playerid, killerid, reason)
{
   if(IsPlayerAdmin(playerid))
   {
        SendDeathMessage(killerid, playerid, reason); // remove it and DeahtList will don't show..
   }
   return 1;
}

I will simply suggest you to try this one. But will not work perfectly it's will send a death message to everyone if the player who died is admin. So in my logic it's definitely not possible.

Why you don't try to send a message to all online admins of who killed who. It's would be better and it's possible by this way.