This is common on new or rebuilt engines or when changing oil brands or adding additives. The copper is coming from the oil cooler. Expect it to continue to rise for the next couple of changes and then it will decrease as coatings form on the cooler. Don't be shocked to see it go as high as 800-900 ppm. For these engines small changes of 20-30 ppm indicate possible problems, big changes of several hundred ppm not.
To be safe cut the filter open an check for metal.
Yes it can but it usually results in only a slight increase in copper, Also most turbo problems are accompanied with elevated soot levels. The way to find out for sure is to do a microscope exam. If not copper particles are visible then it is probably due to the cooler.
What bugs me is the fact that some of the additive elements rose by approx. 700 ppm from 3.5k to 5k; nornally, the trending is the just the opposite with a leveling off.
The 3126's are bad for oil leaks from the oil cooler to the outside of the engine. Check with the owner to see if the cooler has been resealed lately or if the cooler has been replaced due to etching around the seal area.