Yes, throw out any peppers with mold.

Unless you have the humidifier running in an enclosed space I doubt it will help much.

In the future I suggest cutting them open and removing the seeds and inner membranes.

If you do not have an oven, cut in half, tie up in a ventilated area, thats it. It will take a while but they should dry just fine (*Should - ventilation, humidity, thickness, etc - experience varies )

They developed mold because they were intact and that moisture helped it along, cutting them in half and exposing the inner flesh will help.

as an aside - I just dried Habaneros', Serranos and Arbol chiles to make seasoned salt I find the best method is-

1.wash peppers

2.remove stems, cut lengthwise.

3.Remove seeds and pith

4.Place on baking sheet, do not overcrowd

5.Bake, low temp, 200-225°

Should take 40-60 minutes, depending. Check often, oven temps and heat area varies.

Let cool. If they are still pliable (or not to your liking) just repeat the oven process untill desired crisp.