I respectfully disagree and even question how experienced you are with the flight industry. The reality is that the lowest fares are often found on the airline

I respectfully disagree and even question how experienced you are with the flight industry. The reality is that the lowest fares are often found on the airline website and the airline website only and the voucher is good there. There are sometimes but rarely real good offers on these OTAs but it's literally getting rarer and rarer day by day.