Recover Notes after Keep installation

Hi,

I just destroyed my iPhone Notes, with some important financial info in them. I'm pretty ******, and told myself to remember to make it simple next time and not install any unknown software next time before backup-ing the data.

OK well, I do have an iPhone backup, it's not too bad, but I'd like to get fresher data if possible, so I'm asking out for other options (I'm new to Apple).

What I did :

- Opened Notes, don't think did anything bad in it. It seems no local version change possible (via swipe or other).

- Config was : Gmail Note sync on ; iCloud sync off (and Notes "stored as local" in Notes config). My Notes where not sync'ed to Google Keep however.

- So I installed Keep on iPhone

- Notes appeared in "Gmail Notes" instead of "local" notes. Date of lost note suddenly became 27/12/15 (and not some date recent to the one of this post, e.g. 20/01/16)

- Turned notes off in Gmail and on in iCloud

- Nothing found anywhere (Gmail, iCloud, iPhone). Only option seems to be iPhone restore.

Any ideas on what else can be done, maybe they are hidden somewhere in Sync Limbo?

Thank you