If your chameleon is on a hunger strike, try something new like superworms (zophobas morio), silkworms, butterworms or roaches. Unfortunately, you won't find any of these at petsmart. You might find waxworms there, which may get your chams apetite going again.
As far as the dead crickets go, one of the most important aspects of chameleon husbandry is gutloading, and you can't gutload a dead cricket.