@EdN - I know you're extremely eager to get your personal pics off Dropbox. I can totally understand why.
I am not sure if you have considered/fixed this, but I hope the info below will help. I am not affiliated with Dropbox, I'm just an avid user, and a counselor with a tech background. I like helping to resolve problems.
When you install Dropbox, there is an option to 'auto upload' files (including images) from your device/folders. You can turn these off. Also, files can be deleted in dropbox either on your device or on the website.
I get that you're angry and horrified (understandably). And - It's hard to fix anything angry. Do you have someone with some tech saavy that can help you? If not - I can help - and I would be willing to give you 30min free support to find out your next steps and/or fix the problem. We can use Zoom, you can show me what you're looking at, and I can guide you through the steps. You can reach me by email at support at liftnibbles dot com.
In any case, I'm sorry for the horror and shock you experienced. With a tool as complex as Dropbox, it's easy to overlook details and get confused about how to manage issues. But it can be resolved easily, I believe.
Hopefully this will make your life easier.