Skip - "I think this key might go to a lock"
There is no defending her foolhardiness; the only keys that do not respond to locks are (piano keys, computer keyboards keys, typewriter keys, et al). Unless Skippy found the letter “F” from some poor sap’s keyboard, there is no explanation. Furthermore, if she stated that said letter “F” might go to a lock, she may be deemed deserving of a psychiatric holding facility.
Figuratively speaking, one may hold the key to someone’s heart; nonetheless, in such a situation someone’s heart would metaphorically become the lock dismissing that argument.
In contrast, one may find a blank key prior to it being cut for a corresponding lock; however, if that individual fails to notice the smooth, pre-cut surface of the blank key, he or she may be too oblivious for further reasoning.