heh..that sucks already..and yes this is another thing with e3, ALWAYS make atleast a couple more dumps after the first(even if its VALID the first time) same here with one....redumping a second time after let's say 1 hour.....and the tape..whatever on it isn't pressing it enough(that's why u need foam/cartboard on top of e3clip!) it's slowly getting loose..then this happens = e3 coming loose on one end and result is brick if flashing OR bad backup after redump.... because of it.
make sure it's fitted..wich it was as u made valid dump but not good enough as u noticed..so reclip/tape it down and use some foam etc... to keep it pressed down! redump multiple times..compare the backups..all identical? then it's safe to proceed the downgrade.
if u have valid original dump, now first u need to solder Tristate wire and MAKE sure the e3clip can't move while dump/restore/flashing
leave it alone for now..take ur time..i know it sounds obvious but mistake is easy made like this
goodluck on fix