Using iXpand with Infuse

So I got an iPad 8th gen (lightning) running iPadOS 16.3. The iPad doesnt have that much internal space and as I’m going to a place without internet I’d like to download some of the movies to be watched offline I figured I’d go for the SanDisk iXpand Go as it’s supported and integrated with Infuse and all that.

So can someone tell me how to get this stupid overpriced usb-stick working? I have installed their app and it appears in files (although browsing it thru “Files” is a ridiculously limited experience - can’t even open files there? Amazing).

In Infuse it doesnt popup and when I go to add “local folder” and select it in the ‘locations’ pane it just shows the same useless filebrowser like it does when opening it thru Files. There’s no “open” or “add” to Infues. I can do nothing.

So what’s the secret to using this stupid thing?