They mite be just comb sprigs, but not being familiar with the bird, would be worth keeping an eye on and see if it is changing.And as far as his face, are those little red bumps normal?
Yes, you have to make your own assessment on the SLM... to me it's about all the clues, not just a few dry scales. And when I took my suspect to the vet was told I did not have it. This is not the first time Shadrack has disagreed with me on this (or other subjects even). That's why we are here to share our experiences and learn from each other. Even when we have different opinions.
I'm not sure about the red around his mouth. I can't see it super well, but it isn't what I would call normal. While some red can be peaking through the dark skin.. that looks like irritated feather follicles.
I prefer spray over dust as it's easier to get and keep ON the bird. But I would use the dust if I needed to. With the spray you make sure it hits the skin and just a small spritz with feathers parted below the vent, under each wing pit, and to the back of the head where it meets the neck since head lice will not travel to the body. Under $8, wetting a cotton swab if need to get closer to eyes and for chicks. Comes in many brand names and different concentrations. Not considered effective against SLM.
Yes, have your hubs do a door for you asap.
It's important to note that IF it is SLM and you do successfully treat it, the scales may not change in appearance until they are shed off and replaced with new ones.