So the answer is "yes".
A few years back, Iran offered to underwrite Pakistan's entire military budget for 10 years in exchange for Pakistani nuclear know-how. Pakistan turned them down. We still slapped Pakistan with sanctions. Now, of course, they're our ally.
And Sudan offered voluminous intelligence on Al-Quaida in 1993, including several principals in the embassy bombings and the WTC attacks. The US State Department is said to have turned it down, because the conventional wisdom was that Sudan was trying to ingratiate themselves with us by embellishing their information.
But because of our "death cultist" interpretation of those people we were prevented from listening to them and getting them th help us.