yes they are sick or have been poisoned -- I wouldn't feed those sick crickets to your lizards .
I advise that you remove the "healthy" crickets from the tub and set up another tub for them with some fresh greens (buk choi say) and pellets and some carrot pieces in it and quaranteen them for at least a few days (giving them fresh greens daily) and let them purge their intestinal tracts , if they are healthy and active after the purge period they will likely be safe to use as feeders.
The sick crickets should NOT be fed to your pets. (throw them outside on the grass for the wild birds and ants).
The 100% safest course is to ditch the lot and get new crickets from another supplier as Flukers may have a cricket pandemic happening or somehow the crickets from them have been poisoned, so probably not worth the risk to use any of them .