Forum Moderators: Robert Charlton & goodroi
Some of those backlink services have pretty huge indexes, but perhaps not as fresh as Googlebot.
Ultimately, any 3rd party tool might have the necessary depth but not the same snapshot/timeframe as what Googlebot saw. Even if every single conceivable page was fetched by a 3rd party tool, every hour, you can't be certain it's going to correlate with what Googlebot saw.