The center part of the stems is soft, the outside is more hard and though; given time, the center will decompose and give you a hollow look. I would be concerned of some insects (borers, etc) drilling into the main stem via those holes though.

Good Morning Luis ~ Thank you for your thoughts! I did not observe any sap bleeding anywhere around the area of concern nor did I see any suspicious insects. Last season there were tiny ants around & all I did was put some ant-hotels around the base of the tree.
When I took a few sticks I trimmed to show the guy at the nursery along w/ these same pix I posted, I was told to just trim off all the dried branches & did not advise to do any treatments. I might take these pieces of sticks to another nursery for a second opinion.
If you look at the 2nd pic - some canes are crusty but the younger thick canes are smooth as expected.

Thanks again!