Yes, that is the factory engineering firmware, I've already tried flashing that to toggle the OEM unlock, this does result in RMM/KG changing to "checking". From there, tried flashing TWRP ported from another J7 variant with the same hardware, the flash did not even attempt to work, always resulted in a fail in Odin, even when using Cosmys Odin and modified Odin. Even tried patching .img files using Magisk then flashing those, no success, it would give a "PASS", but it would give a SW Rev fail when the device tried to boot and then went into a panic mode. Then I had to boot into download mode using a special combination and release of the buttons at just the right moment then flash back to the stock firmware. No matter what approach I tried when patching, mixing, porting, flashing, nothing worked.
If you go back a few pages in this thread, you will see an entire discussion of the whole process when we were trying to get it to work. When I said that tried everything, that literally meant "everything", as in, everything. The only option I haven't tried is to get access to a eng root .img then flashing that but good luck finding one. You would have to pay a shady website to get it and then it would have no guarantee to work.
What I think you have is a device that someone tried a FRP removal trick on but didnt know what they were doing and couldn't get it straightened out so they sold it.
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