PO411 code related to turbo cutoff valve?

I brought my GTI 1.8t into VW service for a check engine light. Service
tech said it showed a code of PO411 which means an incorrect flow in the
secondary air system. They said I needed new vac hoses and a new turbo
cut off valve to the tune of over $700. I baulked at the repair because
my turbo seems to be running fine. I took it to an independat who said
all I needed was new vac hoses. Car has been running great ever since.
Is the turbo cut off valve involved in the secondary air injection
system in any way or was VW service just trying to rip me off?