Is there a way for two users to make development builds on separate accounts for one app?

Tech stack: React Native + Expo. We are using two solo developer accounts (not a business or team account).

Context: Friend and I set out to make an app together. Friend created app and set it up on Apple.

We worked on it together. He controlled devops (builds and submission).

Friend no longer can commit to development.

Wants to transfer to me. I create apple developer account.

After app transfer, my phone (deviceid) underwent a 14 day soft ban preventing builds. That has since been lifted.

There seems to be something in place preventing me from making dev builds on the original dev bundleid. It says it's still owned by him despite the app transfer.

Bottom line: what needs to happen so I can make dev builds?

Nice to have: we can both make dev builds under the same bundleid