Um, Cricket, I don't think any of those things will "kill" the protein. Only 600 degrees for 30 minutes or more will do that.
BUT these things, after a good soaking to soften any dough residue that may still be on them, can be cleaned with good old soap and water, and that's all you really need.
Not sure what a grain mill attatchment is or looks like, but unless it has tiny holes (such as a strainer has), it should be cleanable. The dough hook and mixing blade - no problem.