You may also want to ask this of /r/askanthropology. Dating of Paleolithic art is problematic and often built on the following assumptions: we know that modern Homo Sapiens did not arrive until after 40,000 Before Present (BP); there is a lot of old art; Neanderthals did not make art; therefore this art must date to a time after 40,000 BP. This is a circular argument that is immediately suspect.

Dating of artifacts within caves with art may yield dates that coincide with modern Homo Sapiens, but that does not mean that artifacts and the art date to the same period. There have been repeated attempts to reevaluate Paleolithic art, and the result has been that some examples seem to be associated with Neanderthals. See this site website, for example.

All that said, most reliable efforts to date Paleolithic art lands it squarely in the Upper Paleolithic at a time when Neanderthals were either gone (or subsumed) or they were restricted to extremely remote pockets of Europe. For all of this, we can conclude that at least "some" (as your question proposes) art was Neanderthal; that most was created by later "modern" people; but that it is clear that Neanderthals were sufficiently human to create art.