I had a bit of a rummage around and a few things seem to be the case:
a) you are right that you should not have to uncheck all three. just the podcast should do. I'll have a look at why that is. Having said that, that's not the main issue (and you clearly found a way around that one by unchecking the other 2 as well. so far so good.
b) whichever way i am searching the itunes api
or in its simplest form:
or variations thereof
i only ever get one result which is your podcast and it does not seem to be subdivided into tracks
if you can find a way ( see the documentation here http://www.apple.com/itunes/affiliates/resources/documentation/itunes-store-web-service-search-api.html ) to return more than that one, please let me know.
essentially - from what i can see - the iTunes api does not return a tracklist for a podcast as they are considered tracks and not albums (which have tracks/songs on them)
(itunes page: https://itunes.apple.com/us/podcast/techstuff/id282795787 )
returns only 1 result in the api call , but clearly has many tracks when i go to the itunes page.
same goes for your podcast.
Note though, that itunes calls them Items whereas when i do the same for a music album
letssay: https://itunes.apple.com/us/album/se/id129169609 - they are called songs
I have no idea why apple decided to do it that way and I don't think I can find a way around that (unless, as mentioned above, you , or anyone who reads this threat, can find me an api call that returns all these "items" in a podcast......
sorry, i dont think this will work unless you make all the "items" in your podcast distinct podcasts (and then use an artist id with your itunes-lookup-widget) or make it an album with tracks/songs
i know that's not exactly what you want to hear, but at least it might explain whats happening