I have android phone and have been using VLC for years. It sees all my videos that are on internal memory and on micro SD card.
My friend is a VLC user on his PC and Mac computers at home and I suggested him to install it on his iPhone 8 with latest iOS.
After installing VLC he the app cannot see any of his videos that are on the phone. He just wants to use it as player of files he already has in his iphone and to check resolution of videos, etc... No wifi, syncing ..straight up basic use.