[TECK]

... but some how I was able to solve the problem there.
What exacly you solved? Is the test board working properly?

So basically make a fresh installed test board and then merge the 2 databases? Can I use impex.
No, use MySQL Administrator to create a backup of the live database.
Once the databse file created, import it into your test board to see if you can replicate the same errors like you have now online.
You need to install PHP, MySQL and a web server into your PC, so you can replicate exacly the online conditions. Do not use a test board on your live server, you will not be able to create 2 databases with teh same name and 2 users with the same info.
If you are not familiar with how to setup vBulletin on your PC, I will update my popular tutorial to reflect the latest changes.
Just make sure you DON'T use those crappy pre-made all-in-one packages that install PHP, MySQL and Apache for you. They are the worst combination possible, you don't learn nothing.
Let me know what OS you run in your PC, I will tell you what to do here in this thread.
(Let's hope you have Vista Ultimate/Business, it will a breeze to install everything manually )

I do not see APC, eAccelerator or xCache installed. I was using this cache system ...
Ya, the hack is well coded. Still, don't use it.
Instead, install MemCached for your vBulletin datastore and xCache for the PHP files.