Transferring "deleted" data from Dead Dropbox Account to iCloud

I have a problem. I was using a free Dropbox account to backup files etc but then switched to iCloud, where I pay for 50gb storage. Trouble is I ignored all the messages from Dropbox saying "you are over your storage limit" and they have now frozen access to that account and have added a message saying "your files may have been deleted". I think they are still there, in some form or another, as the dropbox storage indicator shows it is still over the limit. I want to clear the files out of dropbox and save them to iCloud but Dropbox will not let me view, access, move or restore them it just keeps saying I can pay 4148 for an upgraded plan (with no guarantee that I can get the old files back). How can I get the backed up files over from Dropbox to iCloud?