Unlimited Ultimate plan calling questions

A brother of mine has gone abroad for a month in southeast Asia. He's staying in one country throughout that entire month so our family modified our four line plan of 4x unlimited plus to 1x unlimited ultimate and 3x unlimited plus for the duration of his trip there.

We've already disabled wifi-calling altogether to prevent any local calls he makes there being routed to the US and being classified as an international long distance call. We also turned on roaming in the cellular data settings so he can connect to the towers there and use the 15GB of data allotted as part of the unlimited ultimate plan.

I understand calls he makes back to the US that he initiates on his end with his current American number is included free on his plan. **However, if one of us in the family were to call his American number on our unlimited plus plan, would we be charged a different rate trying to call him as he is technically abroad and not in the US?**

I've tried checking the calls logs/usage in the my Verizon portal and when I called him, the destination is PSDN PSDN, CA, so the portal doesn't recognize his location as being from abroad. And when I check his calls log data, there is nothing recorded so far (too early into the bill cycle).