I have a computer I’m working on that crashed and they have pictures from the last 7 years on it. So I pop their hard drive into a portable HD adapter and try to access the folder with all the pictures.
I went in and manually changed stuff on the security tab of the folder to allow every account to do anything to folder/files. User (me) is also there.
You could try Unlocker. I’m not sure if it will work, but it’s worth a try. I’ve been using it on various machines for a few years and it seems to be safe. Use “Unlock All”, not “Kill process”.