All I can do is most the method, which probably you already know. If it's a matter of them not resonding there is nothing I can advise except to keep trying. Note that it's Podcasts Support you should be contacting, not getsupport.apple.com: https://podcastsconnect.apple.com/contact-us
Here, for what it's worth, is the method:
It is possible to transfer the ownership of a podcast to another Apple ID: poster tcarreira did this and has posted the method:
0 - Contact apple support from the current owner of the podcast: Contact Us -> Podcasts(My Issue Is Not Listed)*.
... wait for them to answer with further instructions and a code...
1. Insert the authorization code “xxxxxx” in the <itunes:keywords> or <copyright> tag.
2. Verify that your Apple ID is activated.
3. Obtain the direct link to your show on Apple Podcasts.**
4. Customize the statement below, and paste it in your reply to this message.
I authorize changing management in Podcasts Connect and access to Podcast Analytics to the account [Apple ID email address]. As requested, I have inserted the authorization code in the [specify tag] tag.
Paste the direct link to your show on Apple Podcasts
*Go to Apple Podcasts for Creators and click the 'Contact Us' link at the bottom of the page.
**To obtain the link in Apple Podcasts app (Mac - Catalina) find your podcast and click the three dots icon to the right of the 'Subscribe' button and choose 'Copy Link'. In iTunes - control-click (Mac) or right-click (PC) on the podcast image (or where it should be) and choose 'Copy Link'.