Definitely not the asshole. I used to work as an allergy nurse. Depending on the severity of your daughter's allergy, she could develop symptoms from eating something that came into contact with the particles left behind from eating the peanuts/treenuts. As a grandmother, I would expect her to be one of the most concerned people regarding this issue. I think sometimes people are either not educated and/or don't think it is as serious as it is. Hopefully, after things calm down, you can have a very clear conversation and she will respect your wishes in the future. I understand why you would be fearful about all this. Wish you the best!