I've had a similar experience. I used Opera for many years on my PC, and now am using Opera for Android on a Samsung Galaxy Tab E tablet. Also I have been using the Opera VPN and Opera Max. The VPN on the tablet did not work and constantly disconnected. Then Opera started crashing immediately after opening. Now Opera is totally frozen. Like you I have many saved pages that I would like to be able to rescue (although I don't have hundreds like you do).
I am wondering if all the saved pages could have caused the freeze? I do not know how I could use the Path that was suggested to access the pages if Opera is totally frozen. I am wondering if you have discovered a solution to this issue.
Concerning the VPN, it seems to work pretty well on PC. I am not sure about the indicators however. If the VPN button is blue, it is connected. If it is gray, the VPN is off. My question is about the yellow-tan indicator, which says your choice of server is not available, or they are working to solve the problem. If you do a test at this point it shows a location in the US--but are you still protected by the VPN???
But, right now I am doing at the test at whatismyipaddress.com. The VPN button is blue showing that it is working, and claims to be set to the "optimal server", but the above website shows my actual immediate physical location in the US.....NOT GOOD.