They didn't pay their developer and copied the whole commit for them to be able to use it. This is a clear sign of a "SCAM". This is now their Official Development page : https://github.com/BitcoinInterestOfficial/BitcoinInterest . It was updated last year.
These guys can't be trusted. Don't be fooled by airdrops and forks. If you buy into it, you'll lose what you have.