I no longer live in this area but I’m very familiar with it. I think a stranger abduction or hoax are remotely possible but I wanted to put out some possibilities I haven’t seen many people mention. Everything is MOO and I’m just suggesting possibilities, not arguing that any of these are definitely what happened.
1. There are homes on the other side of the treeline she disappeared into. She may have wandered into someone’s yard and been mistaken for an intruder by someone who harmed her (then hid her instead of calling the cops when they realized she wasn’t armed or a threat). If there was a child, they could have wandered away from one of those houses. Maybe she was found with the child by the parents and they thought she was a kidnapper, or the child was unrelated to what happened and is now safe at home, but the parents haven’t come forward because they’re afraid of CPS (if there were past incidents or drugs involved).
2. Animal attack. Maybe she screamed when she realized what she thought was a child was an animal? It would be a weird thing to happen there, but black bears and gators are occasionally seen around Birmingham. She was close to a subdivision that is literally built on a swamp that they turned into a “lake” (look for “LakeCrest” on Google maps) and a lot of the other subdivisions have their own manmade lakes, so my guess would be a gator, though a bear cub seems more possible to mistake for a child. Bobcats and coyotes are much more common but I don’t know if they’re big enough to drag off a whole adult human.
3. You can hallucinate without having a whole psychotic break, for example due to sleep deprivation. So the child could have not really been there even without her having other symptoms consistent with mental illness.
4. Someone asked about people in the woods. There are people living in the woods in the area but I don’t know if they were in that exact spot. They usually stay well-hidden and a narrow strip between a yard and a freeway doesn’t sound like a likely choice for an encampment.
5. This would be an incredibly bizarre choice for a location to set up an elaborate trap with a doll/child for bait. I can’t overstate how weird it would be. You would only have to go a few more miles down 459 to get to an area where there are a lot more woods and less traffic, cameras, and witnesses. Sometimes people do bizarre things so I won’t say it’s impossible but it’s unlikely.