Can you resave the maps and see if they are loaded in the app?
Can you share one of the maps that are not displaying in your org?
I'm also interested in hearing about any potential solutions because I seem to be having the same problem. Though in my case I'm just trying to get started with Collector. I published a feature service, created a web map in AGOL, made it editable and shared it with my organization but yet when I open Collector I get a message that says "You don't have any maps for use with Collector." Thanks for any insight.
Also, Ken would you mind posting the link to the Community Art walk through you mentioned? I just tried searching and couldn't find it but maybe it would be helpful for me since I'm just getting started.