i bought a new moab this year, and it came with a sts and yours should have to. i got mine from martins online store and couldn't be happier with it. those 2 strands could be broke under the serving somewhere. if the string stretches enough to take up that much slack your cam is going to be out time quite a bit. i would call customer service and get the sts and a new string
cutis
2009 alien x camo, 09 x all black , 2010 x carbon fiber
2010 nemesis camo, 2011 nemesis carbon fiber,
2010 onza 3 camo,
2010 pearson legend black riser camo limbs