Is footage still kept if cameras are taken down?

A few months ago a friend of mine got into a very messy argument with her spouse which resulted in her having to stay with me and then hastily move out the next day. Her partner was super controlling and had 4 security cameras up (I know this isn’t helpful but I’m not sure what brand or type but I know he uses an app to look at them) we took them down the next day so we could move her out without him seeing.

She has the cameras, but would it be possible to access the footage from the night of the argument without having access to the app/account he uses? Or is this a long shot?

I’m also unsure whether he would have deleted the footage through the app and if that deletes the footage on the camera.

I can update with more info on the camera brand/type, but I wanted to check if this is a potential option before I ever bring it up to her.