The single best way to make sure your Title is what you want it to be EVERYWHERE is to use it as the blog title (assuming you are using WordPress to publish your podcast) or the TITLE box in whatever podcast service you are using. The Best way to make sure your “shownotes” are the same everywhere is to use it in the main post content box.
There are, in Theory, ways to specify for different places different titles, post content and whatnot, but Apps do not have to follow those extra tags. RSS is a standard and apps and directories can choose what they want to use and what they don’t.
Apple, for instance, does not USE the Apple Title tag in “iTunes” desktop or the web preview of Apple Podcast listings. Only in the IOS App. (weird I know). They also do not use the “iTunes Image” tag ANYWHERE in their system other than maybe search preview. No way to force it.
Sorry for the mini-rant.