I do not know whether this will work on modern iPads, but........
Several years ago, I needed files back from an old 2GB iPod. I discovered that all photos and music files were available in the directory into which the iPod had been backed up on my iMac (rather than a PC) using iTunes. There was no indication from the name as to what each of the files was. I seem to recall that typically the name was a string of about 15 digits - certainly, there were no extensions. However, based on the file sizes, I was able to guess which were image files, which were music files (there were no videos in those days). And then I was able to open each in an appropriate app - and resave with a meaningful name.
You may be able to do something similar if you can backup the iPad somewhere and examined backed up files. But whether the backup will back up the files from within the VLC streamer app - as opposed to the vanilla iTunes files, I do not know.
Or, you could buy one of the apps that purports to allow you to extract files from an IOS device. You might find one that allows a 'trial' to see if it does what you want. I have never been persuaded that they would work properly, and have been too cheap to cough up!