Unless it's fabric pre-70's vinegar won't make a difference. Back in the 70's dyes were changed to be more environmentally friendly, no longer using vineyards to neutralize the acids. I would wash it in a washer & regular detergent and keep washing, rinsing until there is no more color lost. Sometimes a fabric doesn't stop & you just have to replace it. I've used Kona black many times & never had it bleed.