Pretty sure after reboot you need to continue in recovery to allow it to complete FV2. Also, did you install AptioInputFixB2-NoPointer.efi first?
Also as a PS: Before this fix I had partitioned my main drive and put my home directory into an encrypted portion and had a dummy account which I used to boot into and decrypt the partition before logging into my real user account. That was a pain, but worked. In 2017 not encrypting your files is insane.
I didn't do any of those. Just enabled it, and it stopped booting.
I am going to let my full disk backup finish before having another go at it. Gave me a heart attack when the whole thing stopped booting. Thankfully fixed it via Recovery partition and manually cancelled the encryption.
Did a fresh install of High Sierra just yesterday, followed the normal directions from tonymac, then when I was done put AptioInputFixB2-NoPointer.efi in /EFI/CLOVER/, turned on Filevault and it's working fine. It would be nice if AptioInputFixB2-NoPointer.efi was standard instead of having to track it down.