Upload from phone

Hello, I have an iPhone 15 pro max and I’m trying to upload a 4k video file onto the app from an external ssd via thunderbolt 4 cable. However, unlike when I connect it to my pc, I can’t find the file when I browse. This is what I ran into when I shot with the 4k pro res settings in video on my iPhone, shot directly onto the external ssd from the iPhone. Is it possible to upload these files or must I use a computer? Any help would be greatly appreciated, thank you!