Dear Miss Snark,
You might not be the person to ask this, but I'm not sure who to approach. And since I already know you (sorta)...
Have third-person narrators gone out of fashion? My writers group says anything told by a "narrator" (as opposed observed or thought by a POV character) is the author giving information to the reader, hence "author intrusion."
When I studied fiction in college though, it was accepted that the "narrator" was often someone other than the POV character, though he/she was not always defined.
You can do anything if you do it well. Third person narrative included. Third person is telling, but not in the same way that "show not tell" is objecting to. It's hard to do well.
Here are three recent books that do it very well:
The Whole World Over by Julia Glass (I loved this)
Company by Max Barry (no one writes better corporate satire. He's absolutely the best)
Triptych by Karin Slaughter