The answer is probably yes.
Winning Setanta would get you €150k prize money, and probably no more than an additional €20k all-in-all in ticket sales, merchandise etc.
Therefore - even if an individual player could be single-handedly given the credit for winning any trophy (extremely unlikely for anyone bar the likes of Maradonna, Pele and Keane in their prime) then turning down €300k in the hope of winning €170k would be very bad business by any judgement.