If you have two accounts, how are your 5 PCs configured for those 2 subscriptions. If they have all been activated with the same LiveID, a hub in your Circle should see all 5, as long as they are on version 2.0 and none are using the beta code.
Technically, they should be configured to not exceed 3 PCs in a Circle, so you would have 3 shown on one hub and 2 on another hub for the 2nd subscription.
So, please clarify how they are configured and what versions you are running on each PC.
-steve