[oattes]

I'm seeing this problem now in the stock Krypton RC3. I've checked the debug log and the notifications are definitely being sent when the video ends and the widget addon starts processing (busy circle and log entries). It looks like the logic for obtaining the current set of widgets falls through to the simple cache where it just pulls the last set of widgets (and so the update to the next episode fails). I'm not sure why the logic falls through to the cache, but I'm still trying to surf your code. Perhaps you might have better luck.

Sounds like a race condition to me. I've checked your log but it doesn't contain a part where you actally watched an episode and stopped it.
You should see some entries like "SkinHelper.KodiMonitor --> Player.OnStop"
And right after that a response from the Skin Helper Widgets that it's ignoring the cache and pulling data from the kodi json api.
OR, if it is indeed a race condition you'll notice a reponse like "get data from cache"

OK, based on your guidance, here is a trace from a 'just now' occurrence:
Update: a bigger section of the log http://pastebin.com/sN2qcvs9