It is possible to make a partial major warship hull that is less than 50% structurally complete, missing several decks, and minus major sections such as the entire bow or stern, watertight and launch it. It has been done before.
In the last 10+ years I have not seen the Chinese ever do this on any major program,
I have seen India do it and for obvious reasons (some of which you stated here.
Although given the slow pace and methodical approach the Chinese had adopted for their carrier program, I don't see why the Chinese would wish suddenly do something so precipitous for no strong, program related reason.
Doing so is tantamount to admitting there is a major problem, but getting it launched is less painful than not doing so.
I see no reason whatsoever to move the Chinese to do this...ergo, it is absolutely far fetched.
Besides, with that vessel supposedly being a major carrier, and not even being up to the hanger deck just a few weeks ago...I simply do not see it happening in any case