The following refers exclusively to the data in 2014-08-02-mn-json/bills/mn/2013-2014
There are 6677 "bill" files under the 2013-2014 directory, and some files have roll call data for which yes_count and/or no_count is greater than 0;
but in all cases the the yes_votes and no_votes fields are both the empty array.
For example, in "HF 1054", we have
That is, it is not possible to infer who voted "yes" or who voted "no".
By contrast, for example, 2009-2010/lower has all the roll call details one would expect.
Perhaps this edition of the MN data was released with full knowledge of the incompleteness of the roll call details, but I haven't noticed any documentation to that effect. Perhaps if an edition is released with known or deliberate "gaps" in the data, that could be indicated somewhere.