Hey @matthew7
I had a chat with our Engineering team and they confirmed that it seems like the client can send a message to the gateway service when the meeting ends and therefore calls initiated are stopped.
We were able to create a Feature Request to achieve this via API (ZOOM-885780 internal ticket number for reference) but I can not provide you an ETA at this point. I will keep you posted if there is any movement in it.
Cheer,
Elisa