Problem with multiple spawns

[neiv2]

I have a global that is set to spawn npcs in rows at a castle when the global flag is set to 1. A watcher in the zone checks the flag and spawns the npcs when a pc enters the zone. The watcher is on a two-point grid with a 5-sec pause. The problem is, a new mob spawns at each spawn point every time the watcher moves to the next grid point, and the npcs continue to pile up on top of each other. The watcher is there to control other globals I use as well. How do I write this script so that only one instance of spawning occurs? Do I need to use a second watcher for this? Watcher code is below and the npcs in question are the 999151 group:

sub EVENT_WAYPOINT
	{
	if (defined($qglobals{lord})) 
		{
		if ($qglobals{lord} == 4)
			{	
			quest::signal(999247);
			}
		}

	elsif (defined($qglobals{kingdomfaction})) 
		{
		if ($qglobals{kingdomfaction} == 1)
			{	
			#spawns lvl 65 guards in Hall
, west facing
			quest::spawn2(999151,0,0,1722.50,1556.52,231.25,190);
			quest::spawn2(999151,0,0,1722.50,1593.45,228.75,190);
			quest::spawn2(999151,0,0,1722.50,1655.94,228.75,190);
			quest::spawn2(999151,0,0,1722.50,1694.96,228.75,190);
			quest::spawn2(999151,0,0,1722.50,1755.84,228.75,190);
			quest::spawn2(999151,0,0,1722.50,1795.59,228.75,190);

			#spawns lvl 65 guards in Hall
, east facing
			quest::spawn2(999151,0,0,1674.43,1556.52,231.25,60);
			quest::spawn2(999151,0,0,1674.43,1593.45,228.75,60);
			quest::spawn2(999151,0,0,1674.43,1655.94,228.75,60);
			quest::spawn2(999151,0,0,1674.43,1694.96,228.75,60);
			quest::spawn2(999151,0,0,1674.43,1755.84,228.75,60);
			quest::spawn2(999151,0,0,1674.43,1795.59,228.75,60);
			#spawns lvl 65 guards outside Hall
, north facing
			quest::spawn2(999151,0,0,1795,1880,227.25,0);
			quest::spawn2(999151,0,0,1605,1880,227.25,0);
			quest::spawn2(999151,0,0,1680,1880,227.25,0);
			quest::spawn2(999151,0,0,1718,1880,227.25,0);
			quest::spawn2(999151,0,0,1755,1838,227.25,0);
			quest::spawn2(999151,0,0,1645,1838,227.25,0);	
			quest::spawn2(999151,0,0,1605,1838,227.25,0);
			quest::spawn2(999151,0,0,1795,1838,227.25,0);
			}
		}
	}