5g relay + eero with custom dns

I have my work phone setup fhe T-Mobile internet 5g it’s on att. I don’t want to use my own phone as it’s strictly for work. I am wondering can I use a customer dns; for a glimpse of a second I was able to get LTE.

I have all radios off and 2.4 gz default hidden but eero both on. Not bridge. I keep getting constant restarts.

My employer is not happy.

Alternatively can I run let’s say ivpn with kill switch on gnat and have it only provide me ipv4 or proton vpn.

I fucking hate all the add etc. I’m opted out.

I use next dns for my fiber WiFi which is not T-Mobile but I may try next DNS on the eero.

I run trace routers and it follows a similar route each time …. On vpn on device.

Any thoughts?

Feeling like T-Mobile fucked me here.