I think you're talking about these two recent posts:
- 2 year old user is a new contributor?
- Is it correct that search on AskUbuntu ignores code blocks and inline codes?
These were edited by Shog9 and Adam Lear. These two guys are Stack Exchange employees, so they have network-wide phenomenal cosmic powers and mod diamonds everywhere they go. They don't have much rep on Ask Ubuntu, since they haven't used this site much. However, they have lots of rep on other sites in the network. They became employees after being hired bycontributing outstandingly to other Stack Exchange the companysites.
SE employees tend to drop by when any site's child meta gets a question tagged bug or feature-request since if there really is a bug they'll have to fix it, and if a feature request is to be implemented, they'll have to implement it. They often edit the tags on those posts to indicate the status of the report/request, though site mods also handle many such posts if there's no need for attention from employees. Only moderators can add the red status tags. You're also likely to see employees around when there is a moderator election.
The election of moderators is explained in this page of our Help Center. On new SE sites, mods are appointed by SE employees, but on mature sites, they are always elected by popular vote.
A humble ordinary moderator(!) rather than a Stack Exchange employee will in general have a lot of reputation and badges and suchlike on the site where they are a mod, since many members of the voting community are likely to interpret these as a measure of a user's contributions and commitment to the site. All our Ask Ubuntu moderators have many reputation points and badges.
A moderator on a site like Ask Ubuntu is also a moderator on that site's child meta, as you'd probably expect. There's no way to become a moderator only of a child meta.