This seems too good to be true. If they could actually predict football results with better-than-random accuracy, then why wouldn't they just use this themselves to make loads of money on betting markets?
Well sure, but there are over 2200 games per month and less than 3-5% are the kind of games you are talking about. Super good team vs terrible team (assuming your local home town team is not Barcelona)
69% is a huge number in terms of sports betting. Typically to be profitable you need to be in the 52% - 56% arena to be profitable, so this is significantly profitable