Sounds like it's supposed to be there.
For the GMPP exhaust for the 2.4L, Borla still has them in stock in their "closeout corner" section. Mine was even stamped as a GMPP part.
(If that link goes away, you can also google "borla 17802058".) As of today, they're $249 plus shipping for the complete cat-back.
If it turns out to be a crack or rust or whatever, you could have a muffler shop or any competent welder fix it, probably for about $30-$50 based on my experience. YMMV.
bolt up to the GXP as well, but it's a single-exit exhaust.
Blue-ish 2006 2.4, Werks stage 1 turbo, Borla cat-back, DDM braces, Spec aluminum flywheel, Spec stage 2 clutch, Werks aluminum radiator, some gauges, RKSport hood, Morimoto FX-Rs, GReddy Profec, Norm's fenders
'07 GXP, RPM Stage 2, Solocatless downpipe, TCE Wilwood 6 piston front brakes, 4-piston rears , Stainless brake lines, slotted/drilled rotors, BC Racing BR coilovers, Performance Autowerks intercooler, DDMWorks CAI, charge pipes and braces