The Premier League giants were initially handed a two-year suspension from Uefa competition and fined €30million in February after being charged with "serious breaches" of Financial Fair Play (FFP) regulations.
However, City always maintained their innocence and launched an appeal with CAS to quash the punishment that was officially upheld earlier this month, with their European ban lifted and fine reduced to €10m.
And the written reasons - compiled in a huge document totalling 92 pages - for that decision released on Wednesday appeared to suggest that City could have avoided such a drawn-out process had they presented all the evidence made available to CAS during the original Uefa proceedings.
CAS indicated that witness statements from senior City executives as well as a letter from club owner Sheikh Mansour - all provided to CAS but not to UEFA during the first process - could have swung the original verdict in City's favour.
"The panel cannot put itself in the shoes of the Adjudicatory Chamber at the time of issuance of the appealed decision, but it finds that the possibility cannot be excluded that Adjudicatory Chamber may have reached the same conclusions as the panel in the present proceedings, had such evidence been made available to it," the decision said.
It added: "The appealed decision is therefore not per se wrong but, at least to a certain extent, is a consequence of MCFC's decision to produce the most relevant evidence at its disposal only in the present appeal proceedings before CAS."
CAS said it was "particularly serious" that City had not provided the original versions of the leaked emails to Uefa, having publicly relied on the defence that they were taken out of context.
But City had argued that Uefa's process was "flawed" and prejudicial, previously seeking to have the case against them thrown out.
When the two-year ban was announced in February, City said they had "always anticipated the ultimate need to seek out an independent body and process to impartially consider the comprehensive body of irrefutable evidence in support of its position".
City had been accused of circumventing FFP rules as leaked emails suggested sponsorship deals involving Etihad and Etisalat were in fact largely funded by owner Sheikh Mansour, with Uefa claiming the sponsorship deals had been exaggerated to the tune of £204m.
But CAS found that the case involving Etisalat was time-barred, and said that while allegations relating to Etihad were only partially time-barred, the alleged wrongdoing had not been proven by Uefa.
The panel found "there is no doubt that Etihad fully complied with its payment obligation towards MCFC and that MCFC rendered the contractually agreed services to Etihad in return...
"There is no evidence that agreements were backdated or that MCFC otherwise retrospectively tried to cover up any alleged violations following the publication of the leaked emails."
The reasoned decision also reveals that City argued the fine should be reduced due to the ongoing coronavirus pandemic, taking into account the effect that it "has and may have for years to come on stadium attendance".
But that argument was dismissed by CAS, who said: "Although the landscape for football clubs has altered since the issuance of the appealed decision, MCFC does not argue that it is in a dire financial situation because of the pandemic.
"The panel finds that the imposition of a fine lower than 10 million euros would not be a sufficiently strong deterrent and that MCFC's failure to cooperate with the CFCB investigation is to be strongly condemned."
Also contained within the CAS document were details of the Premier League rivals that filed an application for intervention for the "limited purpose of opposing any possible application by MCFC to request a for a stay of execution of the appealed decision".
According to CAS, that number included Arsenal, Chelsea, Liverpool, Manchester United and Tottenham as well as Leicester, Wolves, Newcastle and Burnley.
City are due to resume their 2019/20 Champions League campaign with the second leg of their last-16 tie against Real Madrid at Etihad Stadium on August 7.
Pep Guardiola's men lead on aggregate following their 2-1 pre-lockdown success at the Santiago Bernabeu in February.
Additional reporting by the Press Association.