OEMINFO partition is partition 5, it is what we used to called IMEI partition. That partition also stores your SN (the one you find on the back of the phone when you remove the battery). The unlock code depends on both, your imei number and your SN, so if they don't match it won't work. I will try to get you an unlocked oeminfo.
The bootloader state is stored in oeminfo partition, the bootloader partitions are not altered when you unlock it with the official method. So if you copy the bootloader from an unlocked phone to yours, it will still be locked. The only way to do what you are asking is to use the oeminfo partition from another phone that has unlocked bootloader, and that will make you lose your imei number after installing an update.app.