I can understand that you may be slightly miffed, Jamie, but my opinion is that you are overreacting. This is a political song using the format and some of the words of the 'Wellerman,' but that does not make it insulting, any more than the original song was praising the family, in that it was just a song about waiting for a supply ship. The fact that it was your ancestors ship is purely incidental.

There is a long folk tradition of using well-known tunes for other songs. It's unlikely that this number will last as long as the original song, so you will have the last laugh, anyway.