According to Alabama State law he should even see the inside of a courtroom. This is referenced to the "Stand Your Ground Law" or "Castle Law"passed in Alabama.
I'm not an attorney, however, I can read.
Your interpretation is a little off. The first section that you highlighted (section (a)(4)) refers only to scenarios where there is an unlawful and forceful entering of a building. That wouldn't be the case here if you've got a robbery on a sidewalk.
The section that you should have cited to is (a)(1). Section (a) suggests that deadly force can be used in defense of self, as well as defense of others, if one of the subsections apply. Subsection (1) states that if you reasonably believe someone is going to use deadly force, then you can legally respond with deadly force.
So if you see someone pointing a gun at someone else (threat of deadly force), then you can use deadly force to defend that person...unless one of the exceptions apply, such as being in a place that you don't have the right to be.
The only questionable part would be this.
How are they interpreting this?
My guess would be that a person has the right to be on a public sidewalk. I don't see any way that they could claim that a person does not have the right to be on a sidewalk. This section is in place mostly to prevent someone from breaking into a building or trespassing on property, then using deadly force as "self defense."