Google says yes:
Dehydrated Death Cap mushrooms (Amanita phalloides)
develop a strong and unpleasant odor, especially as they dry.
While fresh Death Caps may have a faint, honey-sweet smell, this odor intensifies over time and becomes foul and objectionable upon drying. One description mentions the smell as "sickly sweet and rancid when old", while another notes it becomes "overpowering" and "sickly-sweet and objectionable" with age.
Important Note: Even with their strong odor when dried, Death Cap mushrooms are extremely poisonous. Their toxins, called amatoxins, are not destroyed by cooking, freezing, or drying. Never handle or consume Death Cap mushrooms, and contact a poison control center immediately if you suspect someone has ingested them.
I think she needed to choose a very strongly spicy recipe to overcome the smell and taste of the DCs. BW has mustard, garlic, onions and other spices to help deflect.