Regarding what somebody said that not all Rabbonim are experts in the miktzoa of the halachos of names, that is precisely the point. There really aren’t any halachos. These are all minhagim. Even the idea of not marrying someone with the name of one’s parent as far as I know comes from the sefer of Rebbe Yehudah Hachasid which is not binding. (Reasons have been suggested that it would not be kibud av vaem to constantly call someone by his parent’s first name, since one is not supposed to address a parent directly by his name).
As far as the suggested reason of gilgulim goes that we should not make up new names, here is a question: If you believe in the gilgulistic explanation of Hu Pinchas, Hu Eliyahu, Hu Charvona, or that Hasach is Daniel, etc., then clearly we see that one can be a gilgul of another and yet have a different name each time.
So the bottom line is that if one wants to believe in some obscure, possibly kabbalisticly based novel sevara which only a single gadol holds from, while ruva druva do not, and have never even heard of this entire idea to begin with, and which was never practiced previously in any generation, as we have shown that tons of names from all different languages have been used throughout the doros, and even some which have no meaning or derivation in any language whatsoever, as I quoted from the Bais Shmuel on Shulchan Oruch, then one should feel free to do so. However, to make anybody feel bad about it, and moreover to tell somebody to change his name because of this is simply astonishing, to say the least. The minhag since the beginning of time is that parents picked a name after a relative or to express their emotions or hopes for the child. This is how the Avos did it, (note that Rochel named Binyomin, Ben Oni, since she was in her last minutes of life, a very sad name remiscent of aninus (aveilus, rachmana litzlan). I think the Artscroll Bris Milah book says that Hashem guides parents of each child to pick out the right name. There is no reason to believe that Hashem has suddenly stopped helping parents.