I haven't commented before because I thought my opinion on how to mount the controller was well known (it is documented in the manual). I've personally been using quality velcro strips to mount my controller(s) to the wall in my fish room for 10+ years and have never had any trouble with it failing. Be sure to use the wider velcro strips with strong adhesive, and I don't think you will have any problems.
There are also some velcro like attachment strips that have plastic rods that interconnect. I think it would be nearly impossible for this material to fail. The backing material is a thick plastic with an adhesive. If for some reason the adhesive didn't stick to your wall, then the strip could be screwed to the wall instead. I don't know the brand or name of this product, but have seen it in hardware stores. Maybe some else has seen it, and give the name/brand
Curt