Do not feed baby food as it is very high in sugar as mentioned. I would also not feed crickets until you have him eating the CGD and then feed crickets just once or twice per week.
How old is the crested? A crested will never starve itself unless it has parasites or something is wrong with it. Did you get this gecko from the same breeder you got your last crested from? Can you take it to a vet to have a fecal done to rule out any parasites?
