1992 Volvo 240 EGR valve and piples

I had the valves and head gasket replaced at 279,999 miles. Recently my check engine light came on. The shop told me it's the EGR valve and some curved pipes that are almost clogged and need to be replaced because the shape of the pipes doesn't allow for cleaning. It's a $1000 job! I checked with another shop and the service writer said they can soak the pipes in a solution and that will unclog them. He was surprised it wasn't done when the valves were replaced. Who is right?