This is huge amount of money. Hire an advocat and pursue this.
Don't wait them to give your money back, act on this.
Beeelzebub is right, you should hire an advocat.
Although an advocate would be sufficient.
Are you sure you had 100 bitcoins? What is your proof? Bitcoin transactions? Bank statements?
If you have that you can probably take them to court for trying to scam you.
Only have one screenshot, with the amount, my account number and my nickname.