UEFA knew about that in 2015 and talked to City about it. It was about payment of image rights. These are paid differently to their normal Schedule E salary, which is subject to PAYE and NI at source. Image rights are paid under Schedule D, where the recipient is responsible for any applicable tax and NI.
Fordham (the company who paid the image rights) was set up in 2013 so therefore it's a reasonable supposition that UEFA saw something in our FFP return around 2014 or 2015 that related to this. Maybe they saw the new company involved, or they saw that image rights had 'disappeared' from player remuneration. Whatever, they discupassed it with us and no disciplinary action was taken by them. The arrangement seems to have ended in 2018.
We don't know the exact circumstances as yet but let's speculate that the image rights payments hadn't been reported to UEFA in 2014. That would be pretty serious I'd say, and having been sanctioned once, you'd expect UEFA to act pretty firmly. Yet they didn't. It could be that had we included them, it would have made no difference anyway. It could be that, under the letter of the law, we had a valid argument for making the payments the way we did (although it may not have been in the spirit of the law).
But whatever the background, UEFA discussed it with us AND TOOK NO FORMAL DISCIPLINARY ACTION. Therefore it's not unreasonable to assume that there was nothing actionable.
In 2018, when the Der Spiegel allegations were made public, UEFA charged us over the Etihad sponsorship but still took no formal disciplinary action over Fordham, even though it was within the allowable time period. Given that UEFA's FFP rules are far tighter than the PL's, it's hard to see how the PL can land this. That's why I've said that the PL charges are UEFA's "sloppy seconds" as it's stuff UEFA knew about in 2015 and 2018 but still didn't charge us with.