getPlayersOnline = function () 
  local playersOnline = getElementsByType ( "player" ) 
  local playersO = 0 
  for count, playerOn in pairs(playersOnline) do 
    playersO = playersO + 1 
  end 
  return playersO 
end 
 
That function is completely useless, you can simply use: 
playersO = #getElementsByType ( "player" ) 
 
About the other problem, try this: 
function Scoreboard() 
    dxDrawImage(X,Y,Width,Height, "images/back.png") 
    dxDrawText("Name", X+60, Y+10, Width,Height, tocolor(255, 255, 255, 255), 1.00, "default-bold", "left", "top", false, false, true, false, false) 
    dxDrawText(getPlayersOnline().."/50" ,X+525, Y-15, Width,Height, tocolor(255, 255, 255, 255), 1.00, "default-bold", "left", "top", false, false, false, false, false) 
    dxDrawText("Ping", X+480, Y+10, Width, Height, tocolor(255, 255, 255, 255), 1.00, "default-bold", "left", "top", false, false, true, false, false) 
    dxDrawText("Geld", X+210, Y+10,  Width, Height, tocolor(255, 255, 255, 255), 1.00, "default-bold", "left", "top", false, false, true, false, false) 
    dxDrawText("Team", X+350, Y+10,  Width, Height, tocolor(255, 255, 255, 255), 1.00, "default-bold", "left", "top", false, false, true, false, false)   
  
  local players = getElementsByType ( "player" ) 
  local playas = 0 
  local playerheight = 20 
  for amt, player in pairs(players) do 
    playas = playas + 1 
    if (playas <= 20) then 
      local ping = getPlayerPing(player) 
        local teamp = getPlayerTeam(player) 
        local teamn = getTeamName(teamp) 
        local money = tonumber ( getElementData(player, "playerMoney") ) or 0 
      if (ping >= 250) then 
    r,g,b = 255,0,0 
      elseif (ping >= 120) then 
    r,g,b = 255,69,0 
      else      
    r,g,b = 0,255,0     
      end       
      dxDrawText(getPlayerName ( player ), X+60,Y+60+playerheight*(amt-1), Width,Height, tocolor(255,255,255), 1 , "default-bold","left", "top",false, false,true,true)  
      dxDrawText(ping,X+480,Y+60+playerheight*(amt-1), Width, Height, tocolor(r,g,b), 1, "default","left", "top",false,false,true,true) 
      dxDrawText( tostring ( money ) .." $", X+210,Y+60+playerheight*(amt-1),Width, Height, tocolor(255,255,255), 1, "default","left", "top",false, false, true, true) 
      dxDrawText(teamn, X+350,Y+60+playerheight*(amt-1),Width, Height, tocolor(255,255,255), 1, "default","left", "top",false, false, true, true) 
    end 
  end 
end