Who is piling on? Wow, what a snowflake.
Again, if you read the GM TSB referenced, there is no repairing the head. It must be replaced.
Sheesh, people can't read these days.
Is the TSB you copied & pasted even "Active"? A internal TSB telling dealer techs to replace a cylinder head doesn't mean the cylinder head cannot be repaired.
How was the Balance Shafts Chain condemned? Did you have Timing Chain noise &/or Camshaft Correlation DTC's to condemn the Timing Chain components?
What with the name calling....Are you 10 years old?