Ponzi Scheme? Half joking because this looks like an interesting concept. But reading your spreadsheet you have a "minimum guarantee" of 10% annualized return. Which is not possible.
It is either a scam or an incredible investment opportunity. We will know in 3 months. If it is a scam, they will keep selling them individually. If it is an incredible investment opportunity, they will stop selling them and be funded by someone who is reading the article today. In the US, their investment proposal likely violates the law by guaranteeing a return.
I hope its an incredible investment opportunity and I hope they deliver what they say they will.