so negated AoG enhancements still stay?
If an Enhancement is negated when it's played, the entire ability is negated (including the place portion).
If an Enhancement was placed somewhere during previous phase, you can still negate the special ability, but the placing of the Enhancement won't be negated (since it completed during a previous phase) and it will remain placed.
Example: You place Abom in my territory. Later I play Moses (CoW). He's negating the special ability of Abom but it stays in my territory. Later if you remove Moses then Abom will start working again.