Does US Manufacturing (In China) help the Chinese worker?

Sure it helps them.  By far their biggest customer for most chinese wares is the USA.  Otherwise you'd have a billion people unemployed instead of just a quarter billion. 

There is a huge dichotomy in china between those who go to cities to work and those who don't.  The majority of the country by area is dirt-poor yet some of the "party" members are the richest people in china and the world.  The only middle ground is in manufacturing or in the educated workforce (programming, engineering, etc).  For most manufacturing in china you can hire 15 floor workers for the cost of one union-scale employee here and each one of those chinese workers generally has 2x the throughput as a single american counterpart.   It's the unfortunate truth and some will take issue with it, but it's factual.    There's a thousand people for every skilled job over there and the pressure to perform drives them to go above and beyond anything we'd do over here.  If they don't meet quota, they'll be replaced.

For educated employees, it's about 5 master's level employees for every 1 bachelor level here.  They all have kids and want TVs and to be healthy and live, just like we do.

The problem is that the US customer at large does not want to pay US manufacturing prices.  Unions, taxes, red tape, etc, have all conspired to keep prices on US made goods much higher than those from China.   The big push in "made in the USA" or "buy american" didn't do much at all because it always comes down to cost.  China has also done as much as they can to keep trade costs and monetary conversion in their favor for a long time and that has been roundly ignored by most of our government cycles under the guise of a world market.

What would bring jobs back is a prolonged recession where a glut of skilled workers would be willing to accept lesser wages to be more competitive with china at large.

You know what's funny?  I just bought a little magnifier that says "made in germany" on it in big letters, but on the box in tiny little script it says "made in china".  It's clearly cheap chinese workmanship, not german workmanship.  But then again I paid 10$ for it, not 100$.  I laughed to myself saying "I bet they named one of their cities Germany so they could get away with it".

I have, and I learned my lesson because of it too.

In china they have no laws against outright lying in marketing.  Occasionally someone gets in trouble with The Party over something big and it all kinda gets more realistic for a bit until it blows over.  It's a culture thing though.  We see marketing as True or Lie, they see it as "buy this stuff at any cost so we can survive".