The short term value of releasing mink into the wild is debatable, even under the best of circumstances. In England, the long term value of the releases was positive.
In the 1980s there were about 70 mink farms with no regulations about cage size or the treatment of the minks. The public was blissfully unaware of this, even after years of protests and attempts to educate them.
Mink farms were raided and reported in the news, and thus the public was made aware. In 1999 the Queen herself announced a ban on fur farming. Hopefully from now until forever.
Today, about 7 farms exist for the primary purpose (supposedly) of raising meat and shearing minks. The minks live a better life before they die.
Since the primary benefit of releasing mink may be mostly public awareness/political, I would suggest an open rescue, where activists rescue one mink with a media camera-person (or their own camera person). Open rescues are effective in Australia, mostly at battery chicken farms.