My mom had a Roku when she lived in San Antonio, TX and had access to Disney Plus. She recently moved in with a friend in Mendocino, CA and that friend gave her a Roku 2 XS since hers is in storage. We factory reset the device and logged in with her account, but Disney Plus is not available and Disney says content is not available. I can’t imagine that this is a region issue, as she had Disney Plus before and whatsmyip shows her in California.
The Roku 2 XS is ancient at this point. It isn't capable of running Disney+ and almost all other newer channels/apps. Do your mother a favor and pick up a cheap Express at Walmart. Your mother or her friend may be able to get a deal if they checks https://my.roku.com/upgrade/ . I'm offered a $20 Express for one of my older devices.
Some channels restrict the number of devices that can access the account. NowTV/Sky does this in the UK (you can pay a higher subscription for more devices).
+1 on previous reply that a Roku2 is old and some channels just won't run or work well, buy an inexpensive replacement model.