tucker-m Currently, there isn't support for following other ActivityPub channels in Funkwhale. It's something we're working on, but it's not there yet.
You can still follow the podcast using its RSS feed in Funkwhale, but native ActivityPub following is a little ways off. We're already looking at Castopod's channel implementation and podcast object to see how we can interop with them, but it will be some time before it's implemented.