Regarding the misting: I have grown many species of Drosera completely underwater for days with no ill effect, and as has been noted, rain does not harm them. But keep in mind, this was in outdoor conditions where maximum light and good air circulation produced very strong plants. Indoors, especially in terrarium culture, these same wet conditions can quickly promote fungal growth which can attack the plants and cause them to appear reddish, listless and without dew. This type of fungal attack is not otherwise visable: nothing shows on the soil. Occasional spraying will not harm them, but long term exposure without air circulation is not advisable.