Those three are required. Science is not inherently naturalistic. Instead, it is inherently empirical and observational. That cleared away. Evolutionists then object to supernatural designers, not just any old vanilla designer.
Evolutionists object to the supernatural.
My contribution to the philosophy of science is this. I show that, when approached the right way, some elements of the supernatural can meet the above three criteria, including the requirement for testability. That requirement has powerful implications, as Godel showed. I clarify the idea, and show that it goes way beyond mathematics to impact the philosophy of science itself, the origins debate especially. I give examples of it.