No no no no... you don't say it this way and get away with just sticking "but no one is 100% sure" at the end.
The sentence above it you're claiming that DMM people know it's going to be these girls in this order by saying "It's going to be", which is very misleading. People read that and they will ignore what you say below it. Either poor/lazy english or don't care to mislead ppl.
It would be more correct to say "I've talked to some DMM people and they think it may be __name of girls__ next" or something around those lines.