F*ck. I'm honestly completely dumbstruck as to why this would be causing bricks. I simply don't see where it even has the potential to brick a device (especially in the way that you mention)
I guess that your only option is to go the hard way, with mfgtool and all:
https://www.mobileread.com/forums/sho...d.php?t=170929
Is there actually anyone (except me) for whom this
doesn't cause a brick? I'm seriously wondering if it's just me, or if my instructions are so misunderstandable, or... I dunno
@diba: Are you willing to give this another try?