I plugged my ITA Matrix itinerary, carriers and flights into BookWithMatrix, exactly as ITA showed them, total price €2516.57. BWM comes back with a price of €4444.28 and gives me only one option for booking: Flight Network. A note at the bottom of the screen encourages me to try all of the travel sites listed, but gives me only the option of Flight Network.
Google Flights gives me the lower price with the exact same itinerary, carriers and flights.
Is this a glitch, or is BWM now receiving commissions from some travel sites that it recommends?