Need a Joomla Website recovered. Server side disappeared. Site still there front end after log in but back end white screen after log in.

I took this joomla 3 website off line a while ago. Host Server help tell me - they have no back up because it was off line. But it must be still there because when you log in front end it is still there. Its a big site and need this website back. Host says has no php logs to see what happenned. You can log in to backend but it just goes straight to a white screen. I did have a free lancer years ago change something I had forgotten about to try and make things harder for hackers to find I think he put a file some where just not in the first look place but cant remember where or even if this is relevant. I know it was just close by from memory just the next file youd look in or something.
May be ftp entrance maybe more helpful. Any ideas?