This should help you.
Read my thread here: https://www.win-raid.com/t9091f2705-Cannot-enable-Intel-PTT-TPM-at-ASUS-motherboard.html
It's a bit technical, so be careful. I had to do this to enable PTT/TPM 2.0 on my Asus Z170-A motherboard.
Would be nice to get an official BIOS update with this configuration, if it is possible on Maximus VIII Hero Alpha, as you just presented it can be done.