No, you need in writing that EasyJet refused to rebook to another airline. Otherwise, EasyJet may allege that it was your decision to buy a ticket with another carrier and EasyJet would have rebooked you if you had given them the opportunity (bad faith yes, but not unlikely).

In fact, I would be surprised if EasyJet actually agreed to rebook you to Air France or another carrier. Most LLC will firmly refuse to rebook to other flights than their own (regardless of any obligation to do so under EU Reg. 261/04)