The problem, though, is that this DBI call is part of a larger module that encapsulates DB access for some tools. It's another layer on top of DBI. My layer doesn't know which items were formerly hex and which were strings all along, so I can't blindly convert.
I could convert, though, if there were a way to know what data I was getting back. That might be another way to tackle the problem, but I'm not sure how to do that either. All I've done so far is just hand back the result array, which works great for everything except these fields.
A fair fight is a sign of poor planning.