Is Andorra truly covered by the mobile select plan?

On Xfinity's destination checker, Andorra is listed as being fully covered for text, calls, & data. However, this forum is full of people who've traveled there with a global pass, and been charged 4 or even 5 figure bills for data use there. Is Xfinity able to actually confirm with certainty (not just the destination search) that Andorra data is complete included with the mobile select plan?