When people eat peanuts they usually touch all sorts of things with hands that have peanut protein on them. If someone who is allergic to peanuts goes into that house and touches some of those same things like faucet handles, light switches, door knobs, the backs of chairs, table tops, etc and then touches their eyes, nose, or mouth, they can ingest enough protein to cause a reaction, and in some people, even anaphylaxis.
You say the peanuts were in a bag in a draw and then moved to the garage. Was the whole house scrubbed down? Probably not. If people in that house usually eat peanuts and if they don't wash their hands immediately afterward, then they are almost certainly getting peanut protein around the house. Some peanut allergic people will react in that type of situation. My child has had multiple reactions including very serious ones from that type of exposure.
I remember your earlier post and I remember the discussion about chocolate. The chocolate could be a few things. It could be she is eating an allergy-friendly brand. It could be she is just missing chocolate and taking a huge risk to eat it. It could be she has a higher threshold and can eat foods like chocolate that have some xcontam. It could she got very lucky and didn't get enough xcontam to react. It could be the chocolate she got is actually OK for her (Hershey's for example is not a risk for peanut allergy, I believe. Don't go by me but I think that's right.)
What type of chocolate did she eat?
What treatment did she get for the breathing trouble?