Simply stated, they don't have enough. I know that offends a lot of people, but it is what it is. If they jump the gun, or treat them more aggressively than the standard dictates, they can be sued for damages.
They have to show that (regardless of her sobriety) she made a decision that (as a result) caused harm to come to Lisa. Like it or not, alcohol is legal and there are no limits on how much a parent can or can't drink. Also, they have no proof of patterned neglect.
In addition to that, there is little evidence of "imminent danger" applying to the wellbeing of the boys.
We could debate this all day. It's not enough. But she ADMITTED she was drunk. But they need to show HOW she is directly or indirectly endangered her daughter, not just that her drunken state may have contribute to harm. But she ADMITTED she 'may have been' passed out. It's circular.
With FBI and LE on this, they aren't going to jump ahead of normal procedure- and they aren't going to ignore it if there is legal reason to remove the kids. They can't just take kids, they have to weigh if it would hold up in court or be considered overly aggressive.
PS- if parading your kids in front of media is enough, then we need to get some celebrities locked up! (light-hearted, I understand the implied sentiment)
ETA- even if they were to be taken from DB, they could be put in the care of JI or grandparents. Not much would change.