If you really want to preserve the Bionoids dub, you can edit the film around the dub itself. OZC-Anime is using that method to the old dubbed VHS versions of the Mobile Suit Gundam 0079 Trilogy currently. They have already done the unedited subbed versions, but wanted to preserve the other version as well.
Of course, I don't know how much you would want to do that, but here is the option nevertheless.