Recover earlier version of fcpx project without time machine

I've been very foolish.

I had multiple versions of FCPX projects in the same event, so I tried moving them to a new library and renaming the current library. Big mistake!

Now the final version of my project is badly messed up (missing links, messed up effects, general distortions...) and I get 'backup not available'. I haven't set up Time Machine, and the Apple support are too busy to respond.

Previously an expert Apple technician showed me how to access the depths of old versions. I badly need to set FCPX back by six hours.

Any suggestions gratefully received