initial set up at an army base

Hello, 

I sent my son a Sonos Roam to Fort Bragg. He can’t use it or even get to the Bluetooth mode because he can’t do the initial set up. Army base Wi-Fi doesn’t let him in. I know he has to be on a home network for initial set up but there must be a way he can bypass this. Thank you for your help! I’ve read about travel routers or using a hotspot but I’m not sure how to explain this to him because I’m not very techie.