other than going through each observation one by one, the closest thing to what you’re describing that normal users can do is to return observations from the observations search endpoint in the API. one of the fields included in the response is oauth_application_id, and although you can’t filter on this field when you make your request, you can parse through the results to find the ones that have a particular oauth_application_id (2=Android, 3=iOS).
only the staff can do this (or I assume someone who can query directly against the database). the only thing normal users can do that i’m aware of is to look through each photo in each observation one by one, which would be super inefficient.
it is possible to query by tag (ex. https://www.inaturalist.org/observations?q=Tineoidea&search_on=tags&user_id=victorengel). i’m not sure what value you plan to search for, but if the number of observations returned is small enough, you could just look through your observations one by one to find exif info.