First you need to add back the “Podcast Embed” custom field to your BDC Podcast collection, but make sure the type is set to Plain Text. Once you’ve got that added, make sure to add only the URL within the Simplecast embed code to this field for each collection item (what I have selected in the following screenshot):

Note: Since most of this URL will actually stay the same between episodes, you can choose to only select the string between ..cast.com/
and ?dark=false
, however most embed fields automatically select the entire line for easy copy/pasting. Feel free to shorten this to only the “unique” portion of the URL if that’s not the case.
Now that you’ve got the unique URL for each of your podcast episode collection items, just head into your Embed Element HTML, select the same portion of the code shown above, click the “+ Add Field” button, and choose the “Podcast Embed” option:


Note: I used the “slug” field option as I don’t have the ability to create collection fields on read-only projects, so in your case the dropdown option and Dynamic Field should be the newly created Podcast Embed label containing the episode URL.
Once you’ve got that added, just save the Embed Element and you should see unique podcasts displayed within your Podcast Collection List. 