Why would DuckDuckGo need to exit? Are they losing money?
There is a financial sweet spot where the contributors to DuckDuckGo are fat and happy and there aren't greedy investors wanting to monetize all that trust.
Google has already occupied the greedy investor niche. DDG has carved out a niche where, I fear, the greatest threat is a lack of money for the people building and maintaining DDG. If they feel underappreciated, they may start to monetize that trust. The DDG team should be rewarded for their hard work.