Semi-false positive on what the issue was, the following works(I need to refactor, but hopefully the gist is understood):
String[] locations=SelectedLocation.split(",");
List<String> locs=new ArrayList<String>();
for(String l:locations)
{
locs.add(l);
}
...
The exception was actually referring to:
.add(Restrictions.in("Division", SelectedDivision))
(adding this for completeness)
.add(Restrictions.in("LocationCode", locs.toArray(new String[locs.size()]) ))