The article appears to confirm that we've lost commercial income due to Nielsn vetoing or revaluing deals. Nielsen were also involved in the original PSG issue over their sponsorship with the Qatar Tourist Authority.
PSG struck a deal with QTA for about €100m per annum but UEFA's chosen consultant, Octagon, valued this deal at €5m per annum. PSG disputed that (and it does sound low) so Leterme allowed then to get an alternative valuation, which Nielsen provided. That was very much closer to the €100m but, despite having been given a much lower valuation by the company appointed by UEFA, Leterme waved that higher one through without a challenge.
It smelled to high heaven and it also begs the question of whether Nielsen tell their clients what they want to hear, rather than being objective.