If I'm not mistaken it seems that you want to make another podcast and have that podcast be easily accessible to your current listeners. Kind of a "one stop shop" for Nunya's podcasts.
Maya's solution is one way to do it but I fear it may become a nightmare to manage over time.
Ericpp's suggestion of using a publisher it likely the future solution for these kinds of things.
The publisher tag is fairly new and there's not a lot of support for it in the apps. Off the top of my head I think only Fountain and Truefans support it.
There's also the podroll tag which is pretty awesome. Again not a lot of apps support it yet.
Here's how publisher works. It's a 2 part process
Part 1
You make a feed with a publisher line
Then a list of remote items
Each remote item represents a podcast that you publish.
Part 2
Then in your podcast feeds you add a block
inside that publisher block you put in a tag that points to your publisher feed that you created in step 1.
What the Publisher Tag Does
When a podcast listener is playing your episode, the podcast app has a reference to your publisher feed.
It can then give the listener a list of all the podcasts that you publish. (pretty cool)
We know that it's authentic because both the publisher feed AND the podcast feed reference each other. That way no one can impersonate you. (so long as the listener is listening to your feed and not some bootleg look-a-like)
The Podroll Tag
In your podcast feed you put a block
Inside that podroll block you put a set of tags
Each remote item points to another podcast.
What the Podroll Tag Does
When a listener is listening the podcast player is aware of the other podcasts in the podroll tag and can surface them as a list to the listener saying something like "If you like this podcast, be sure to check out these other podcasts recommended to you by the podcast host"
Examples:
My publisher feed
https://cdn.kolomona.com//podcasts/publisher-rss.xml

My Lightning Thrashes feed
https://sirlibre.com/lightning-thrashes-rss.xml
Publisher:

Podroll:

RSS++