Personally, I've never heard of Just Dial until now so I am doubting it's that popular. I wouldn't worry about that website, especially if you're not getting anywhere fixing the issue. Just focus on having your clients' Google My Business, Bing, and Yelp listings accurate.
Probably the only citations worth fixing are the ones that you would try to get if you were starting a fresh campaign for a new business today. And if you can't a citation fixed fairly easily, it's probably not worth your time.
New advertising option:
A review of your product or service posted by a Sterling Sky employee. This will also be shared on the Sterling Sky & LSF Twitter accounts, our Facebook group, LinkedIn, and both newsletters.