Devenec, how are you getting the function pointer for vkSetDebugUtilsObjectNameEXT? Since this is an instance extension it should be with vkGetInstanceProcAddr(). If vkGetDeviceProcAddr() is used, and are also using layers, it’s possible the VkPhysicalDevice handle isn’t being unwrapped correctly and the driver ends up trying to deference a layer handle.
Also note this loader bug, which may also be affecting you: Regression and incorrect handling of VK_EXT_debug_utils instance extension · Issue #116 · KhronosGroup/Vulkan-Loader · GitHub