It doesn’t really matter if there is wheat flour in there. That alone can’t decide the bracha it depends on the percentage of the wheat flour in there. (From what I remember learning think it was about the la-hit specifically that the amount of wheat flour in there changes very often) additionally there is a Shaila regarding the way the flour is used since it isn’t really mixed with water to form a traditional sort of dough mixture rather mixed into the chocolate through some other process (has hafrashas challah ramifications as well…) and lastly it does contain rice flour so depending if you make a mezonos on rice that could possibly have a affect on what bracha to make….
I presume that these chocolate bars are created by first baking a hollow wafer and then filling/infusing/covering it with chocolate. (that's how you get a crunchy wafer in the middle

). (If you want to correct me with yedia berura with the exact process, beseder, but until then I think that it is a fair presumption based on the full ingredient list - Nogat filling, chocolate covering, wafer made from
wheat and rice flour mixed with water, sugar, milk powder, cocoa powder etc... i.e. a chocolate flavored wafer)
So you have a sweet wafer, rov flour is wheat, that then gets covered and filled....
A. Why would the bracha on said wafer not be Mezonos?
B. why would covering/filling it change the bracha?