Default [Q] Asus Pad bricked?

Hi, i tried to root my Asus memo pad fhd 10 using this thread
I followed the steps to "6. Unmount /system, Reboot...Done! "
When i reboot the device it get stuck on the Asus logo (boot logo) and nothing happens.

The problem now is that i forgot to put it into debug mode so i can't use any fastboot/adb commands (No devices is listed when i type adb devices).

When i press Power + Volume Up i go into DroidBoot Provision OS where i can choose among these options
1 Reboot DroidBoot
2 Reboot
3 Factory Reset ( Tried this, it will get stuck on boot up)
4 SD Download ( I get error "Error: no detect /mnt/sdcard/"
5 Power Off

I got really no idea how to fix this, any suggestions? Feels so bad to destroy a pad just because i forgot to enable debug mode...