So yeah, the problem here is that the New Static mesh is null on every instance of the actor until you specify it. So your bool isn’t going to give you the result you want because you’re asking the engine if Current Static mesh (nothing) is not equal to New Static mesh (Nothing). Which means it will only read as true if the Current static mesh is specified.
Easier solution would be to create a custom bool called “UsingNewMesh?” and then use this in your opening bool and set it to false by default, run your code off of False, and set the bool to true at the end of your code, after you set the new static mesh. Then every time CS runs it will check to see if you’re using the new mesh, and if not, it will change the current mesh to the new one.