I’m guessing you’re speaking from authority as someone who knows the details of his contract with Chelsea?They didn't treble and he wasn't given anything like that for signing.
If not and you’re just guessing like everyone else then you’ll have to lay out your reasons to think his wages weren’t trebled. I’d have thought he was on about 20k max a week at City and he’s definitely on more than 60k now.
Most players tend to get 10% fixed fee of their transfer fee so it’s not unreasonable to assume he pocketed around 4m from the move.
Happy to be told otherwise though.