The names seem to have become a bit mixed up in some forms of the song, but I wouldn't pay too much attention to that really. You don't tell a talking animal to mind its own business, though; you always have to bribe it, or else make it an offer it can't refuse; as in the Saki story about the talking cat that blackmailed everybody until they brought up the subject of vets.

Meanwhile, here's a link to a Heer Halewijn text with a translation into English. It seems pretty good on the whole, though there are some odd word-choices in one or two places. Best ignore the accompanying notes, though, as they make some rather dubious assumptions which need a good bit of salt to go with them.

Heer Halewijn