Adding multiple Sitemaps from Search Console Data Connector

Issue: We have over 90 sitemaps on average in our Google Search Console account that we want to report on. These sitemaps are added & removed regularly in Search Console using Google's API. Ie. one week we may have 92 sitemaps and the following week we may have 97 sitemaps.

We want to aggregate the numbers from these sitemaps into a single card.

But...the Search Console data connector allows us to select only a single sitemap per data connector.

One approach that we thought of is to create a data connector for each sitemap and then join the data using a Magic ETL data flow. But, this is not manageable since we would have to manually create new data connectors and update a magic ETL data flow frequently to keep up with any new sitemaps that are added to our search console account.

Another approach would be to make a direct call to the Search Console API using an HTTP rest api call (which would give us all sitemaps in one response) in combination with a JSON data connector. I don't think this is possible because you need to authenticate with OAuth2.0 and I don't think you can do that through the JSON data connector.

Is there another solution?

What would be the best approach to solving our problem?