Bulk recording download vs Single download format difference

For our customer, we are downloading recordings (audio, chats, messages, and emails) in bulk. The transcripts from the chats, messages, and emails are JSON format, with emails and messages being zipped.

For troubleshooting purposes, I have created a tool that allows me to input a ConversationId and pull the conversation details, the recording metadata, and the recording for the conversations. The chat, message, and email recordings are in HTML and the formatId property on the GetConversationRecording api allows only ZIP and NONE.

I know there is a transcript property on the Recording object, but it does not contain the same level of data that the JSON recordings contain. If possible, how do I get the JSON transcripts for these types of recordings?