If you still have access to the feed you can make any changes there (including the title) and the Store will pick them up after a couple of days. Currently the feed in use
has a title different from what is in the Store; and the episode file does not download as there is apparently no file at that address.
If you really want to get the entire podcast removed, you need to email them at podcasts 'at' apple.com
<Edited by Host>