When I read the title, I immediately imagined China faking growth at a global scale and maximizing its importance. It's not the case at all:

Of the 31 provinces, direct-controlled municipalities and autonomous regions in China, three have already admitted falsifying certain economic data. Starting with the northeastern province of Liaoning in January 2017, the Inner Mongolia Autonomous Region and the city of Tianjin have said their statistics were wrong.

Of the three, only Tianjing has admitted doctoring the overall provincial gross domestic product figures. Liaoning and Inner Mongolia had padded something else: their fiscal revenues.

I had thought the same but I'm still wondering if it was a proxy to cover something else (ex. ability to pay debt obligations) that would have had ramifications in the global market

Of course they knew about it. It is just when one province do it, others have to do it too. There aren't any Top party members who hasn't been a head of region at least once when they were ranking up the ladder. So not only did they knew, they properly have done it themselves.

Now Xi is trying fix what's wrong. ( Only if you are not reading too much into it )

These numbers came out after shakeups. New local leaders (like company boards after an accounting scandal) want to get their base numbers low -- making their own GDP goals a lot easier to achieve.