There was deception but not from UEFA, that was all Der Spiegel who presented the emails in a way that sold their story.
Failing to point relevant dates out for clarity(context), hoping they'll be missed by their giddy readers(and they were in the large) such as the date of the first email which they led with, along with the fact it was two years before CLFFPR was implemented(did they mention that?), possibly before the rules were even finalised. Which would mean "City were looking for ways around rules" they hadn't seen yet.
The doctored emails you mentioned were two spliced emails and were said to give a distorted view by CAS themselves. Just not enough to dismiss them outright without exploring it on legal basis, which they did and found no proof. I don't believe CAS said the redacted text on the originals were irrelevant or provided no context specifically.