Getting a brick wall from support:

"The number(s) are not active in order for them to move over to T-Mobile or even port into T-Mobile, which is required. this is why T-Mobile does not have access to these numbers."

Email the T-Mobile executive response team. ExecutiveResponse@t-mobile.com

If you get any traction, port the number out to Twilio as soon as you can. Twilio will be helpful to assist with the port, in my experience, as soon as you can get access to port the number out.

Good luck.