There is no bravery is deleting the misc. files from your Android phone because if you are doing so then you are just kicking off your data from your device. And why to delete those misc. files? They are not harming you then why to do so?
Well, once deleting the WhatsApp files can cause a serious problem as it can delete the database files. However, there is no difficulty in retrieving lost misc. files from Android devices of WhatsApp data.
To recover those files, I would simply suggest you to use some third party recovery tool like Android Data Recovery that works effectively to restore all erased misc. files of WhatsApp from Android. This is the one and only way to get back your lost files from Android devices without any backup.
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