Offering the wax worms is only going to do exactly what happened... spoiled and waiting it out! I would continue to offer mealworms and try to entice him that way. If you pop the heads off the mealies and rub the juices on their lips that can often get them to trigger back into eating.

However, it could also be a seasonal thing where he's more interested in breeding then eating. Get a gram scale and keep accurate weights. If he's not dropping much weight I would not worry. They can go several weeks without eating. Drinking is a different story. Make sure he's getting fluids.

HTH!
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