It probably isn't so simple one way or the other. The Open Skies document alleges that the AD government paid the sponsorship, which is where the ADEC thought comes from, I think.
But, at the end of the day, both can be true. 8 million could be paid out of the cash resources of Etihad and the remainder could have been forwarded from ADEC to Etihad specifically to fund the sponsorship. So Etihad would have paid all the sponsorship as Pearce said, but the vast majority would have had to be arranged from ADEC, as the emails said.
Context is everything.
Edit: And if the allegations are anything like UEFA, they aren't questioning that Etihad paid the full amount, anyway. The allegation is that the majority was funded into Etihad by ADUG/ Mansour for which, I expect, they will have no evidence at all.
The CAS witness evidence on this was broad and unequivocal:
Mr James Hogan, former President and CEO of Etihad: “The sponsorship obligations were paid out of Etihad’s own funds”
Mr Simon Pearce, Non-Executive Director of MCFC: "Neither ADUG nor [HHSM] funded any of Etihad’s sponsorship obligations”
Mr Ahmed Ali Al Sayegh, Board Member of Etihad Aviation Group and Chairman of the Board Finance and Investment Committee:
"[Etihad] did not receive any payments from ADUG or [HHSM] or any person or entity controlled or influenced by them, whether directly or indirectly in relation to any of the Sponsorship Agreements, whether by way of advance funding or subsequent reimbursement."
Mr Henning Zur Hausen, General Counsel and
Company Secretary of Etihad Aviation Group:
"All sponsorship fees payable by the Company under the Sponsorship Agreements have been and are being paid from the [Etihad’s] general funds and from sources available to the Company…[Etihad] did not receive any payments from [ADUG] or [HHSM] in relation to any of the Sponsorship Agreements.
Mr Tony Douglas, then Group Chief Executive Officer of Etihad, now CEO of Riyadh Air confirmed that Mr Zur Hausen's evidence was entirely correct and stated:
"For the avoidance of doubt, I also confirm that the sources available to the [Etihad] have never included (whether directly or indirectly) [ADUG], [HHSM], or any person or entity controlled or influenced by them.....I confirm, for the avoidance of doubt, that [Etihad] has never received any money whatsoever from [ADUG] or [HHSM] or any person or entity controlled or influenced by them, whether directly or indirectly."
Sheikh Mansour bin Zayed Al Nahyan in writing confirmed:
“I can confirm that I have not authorised ADUG to make any payments to Etihad, Etisalat or any of their affiliates in relation to their sponsorship of [MCFC], nor have I authorised or arranged or anyone else to make any such payments to them. I can also confirm that I have not made any such payments myself."