The only way to destroy a cam gear is if you beat the hell out of it. I have worked on many of 3.5 liter intrepids and the only possible way that the cam gear got destroyed is that he was try to put the gear back on the camshaft itself (he took it off to probably replace the cam oil seal) and beat the hell out of it to get it on, thus cracking the gear in the process. That's mechanic error; in all the many times that I've done timing belts I have NEVER heard of a cam gear that was destroyed; not even if you dogged the engine, it wouldn't shear.