I am repeating the professional legal advice that I received, which similarly related to a missed onward connection after a flight delay that was the airline's fault.
At the risk of going back to square 1, the OP doesn't have a missed onward connection in his/her case. what they had were missed departures on separate contracts. I too am getting a bit confused by the argument so maybe giving the specifics of the three payouts that you received would be really useful for those who want to make up their own minds as to whether the route you suggest is one that they feel is appropriate to their own cases or not.