In my "Wild Fermentation" book it just says to use the "mother" to start another batch of vinegar (not mentioning the honey vinegar although). Just using soured wine of course for your vinegar, as first is wine, then comes vinegar. The acidity of the finished vinegar correlates with the alcohol content of the wine it was made from. Just let the honey/water ferment in wide open air with your "mother of Vinegar" for a few weeks longer would be my opinion. Of course stir and keep covered with cheese cloth. Of course wild cultures will also get in. Book is "Wild fermentation" (The Flavors, nutritions, and Craft of Live-Culture Foods), by Sandor Ellix Katz.
I've found that. My question is, how much mother? Will a cup of mother be enough for 50 gallons, or do you need a 50/50 mixture of mother and mead? I know both are exaggerated, but I don't know what the ratio is, and haven't been able to find it.
Bragg's brand of organic apple cider vinegar says on the label that it contains 'the mother'. Perhaps you could add a bit of that as a starter/catalyst? I have heard of other people making various vinegars using some Bragg to jump start it. Easy to get in health food stores/natural food markets. http://blogs.villagevoice.com/forkintheroad/braggs.jpg