Are you sure you restored right/yours TS backup?
I have a friend who restored Z1 TA backup to Z2, this things happen so who knows...
It's really odd if you restored your backup on stock fw and something like that happened..
Now I realized you wrote "I had flashtool problems..."
I thought you have problems in flashtool now, that's why I said try with another ftf or another flashtool version...
If you got that, and you did, while you were flashing ftf....I believe you are, unfortunately, right, this is hard brick.
BTW - which firmware you tried to flash?
Sent from my D6503 using Tapatalk
seems it done, right?