It's still a lodging/naming problem. You can name you bin, clip, and timeline, any name you want on your workstation. That part doesn't matter. The shared clip should have the same name for both editors on the server. But if this is a continuing project, it makes sense to have all bins, clips, timelines, projects, and all other media with correct master labeling. Going back for re-editing and footage searches will be much easier. As you are finding out.
As for sharing, you are only sharing the master files, not the actual PP project. Each of you are on a separate computer, working on different segments. Correct? You are using a server to hold the new and old footage for that project. Also, you are using last year's Premiere Pro "project" that was used for the edit. All unedited footage in created bins with all the final timelines that were rendered out. Correct?
I will stick my neck out, say, that your are really not sharing footage. The footage may be on the network, but you are copying it to the local workstation. (Since you can rename the clips, but not affect the clips on the server) Premiere Pro requires to have all media in the same place and on the same computer. Not using the current version of Premiere, but understand it doesn't do community editing as Avid does.
All edit footage and renders would only be on the local computer, not on the server(network). Premiere Pro doesn't work that way. You maybe saving work to the local computer and a copy of the project to the server. You could access each other's project, but it would be missing footage since PP couldn't find it.
If I am correct in all accounts, I would put the new footage in a new bin, labeled with proper titles, descriptions, and any other information required. That new bin would now become part of the older project footage. Would not place new footage within bins with old footage.
I would open last years PP projects, and make a copy with the current date and name that will reflect the edit. Both editors should have the same starting projects, just in the title, user name to show who was the editor. Both would have the same named bins and clip names. The only changes will be the updated timeline and new footage used.
As for the old footage without proper description(CU of Man, WS of Storefront), you really should stay with that labeling. If you changed that, even on your workstation, it will not match up anymore. When someone comes back to re-edit that timeline, the name will not match the original title.
Like I said in the my first post, it's a logging/naming problem. The original footage should have had proper naming and descriptions. It seems that wasn't done. You have seen first hand how big of a problem it is.
To see what each other has done, you have to render out the timeline to a file onto the server. You couldn't access each others timeline.
Disclaimer: I really don't know how your network, computers, projects, original logged footage, newly logged footage, and actual workflow that used in the pass, but just using my knowledge when overseeing a small facility. This a problem that need to solved in person to fully understand. Or have a complete picture of the workflow.