Does Wheel Cleaner safe for wheels, Manufacturer says not to use any cleaners.

Yes, this product is totally safe for both your tires and your wheels. All we recommend is to follow the instructions such as don't use on hot wheels/brake components right after driving, and to give it a good rinsing and drying afterwards.

HOWEVER, if VMR is adamant about not using cleaners, and you are having tough time keeping them clean, I would suggest having a ceramic coating applied. This makes cleaning wheels super easy, sometimes even just a spray of water can clean them. I can't endorse any ceramic coatings, but there are many available and you can just research to see which one best suits your needs.