I would assume the phone is locked and all data is encrypted. If this is true, you will not be able to recover files from the phone without unlocking it first.
However, it's almost impossible to setup a phone these days without setting up various online accounts and syncing data. There could be copies synced to Google photo. Also look at Sony, Microsoft OneDrive, Dropbox etc.
Fortunately it's only photos, these days we virtually run our lives from our phones. It's a good lesson for the future that whatever is on the phone is not recoverable and has to be backed up.