Maybe.
I might have missed one but the biggest contract for an RP that off-season appears to have been 4 years $31mill for Darren O’Day. Certainly Kimbrel gets more money and probably the same years (five year deals for relievers are still rare). $60-$70 mill would be the range. But what’s your point?
Really what it looks like is Dombrowski escalated his price to convince San Diego to sell. That means yes, he had to overpay. If San Diego was dumping salary, he really went overboard. And for a team with as many needs on pitching as the 2015 Red Sox, spending all the allowance on a closer did not look like a good idea.