I defer to
@AaronSC's experience, as I've not had an oaked Vignoles.
Dredging my memories, since I haven't had much Vignoles in years, I seem to recall that "dry" Vignoles I tried were actually off-dry. I made it once, and used 1 quart reserved juice to backsweeten 5 gallons. [My version of "sweet" is quite dry to most folks.
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A small amount of sugar (SG 1.000) can produce a large change, so don't rule that out.
Making my above advice more specific, try oaking 1 gallon. The ratio for oak cubes I've used is 2 oz for 5 gallons, so use 0.4 oz in a gallon, or maybe reduce to 1/4 oz. This way you risk only 1 gallon. If it doesn't work out, you have 5 bottles of cooking wine. If it does work out, you can either blend the oaked into the non-oaked, or add oak to the remainder.
My experience is with NY Finger Lakes white hybrids. I found that with the exception of Seyval Blanc and Vidal Blanc, they benefit from just a hint of sugar. Vidal is typically used for sweet wines, but the few bone dry ones I had were quite good.