AFAIK, it’s not a listed 3rd Party app. If it’s web based there should not be anything stopping you from adding it as a Web Tab within the Teams channel like a website which may be a workaround. May also be worth reaching out to Kerboodle support and seeing if there are any plans to integrate them like other apps such as Flipgrid.
The most authoritative list I have seen apart from the Admin Centre where all apps are controlled is here
