EDIT: I was thinking more about what I posted so I checked out the Nicehash website as it did seem hard to believe they had such a high withdrawal amount, and the first thing I seen was "Payments from 0.001 Bitcoin". So something doesn't add up with the OPs story.
I've been using Nicehash for many months now and it has been my experience that they do not pay out less than 0.01 BTC.