The only policy is having the physical card or having it loaded onto your phone, and if you're caught giving it out to people you get in trouble (fired). There's nothing in there about the barista needing to "verify" it!!
WTF kind of power trip was that? I'm so sorry. I know its a lot of extra stress and extra work but I encourage you to go back in and \~lightly\~ Karen out. Just focus on how it made you feel and how the barista thought they have any right to ask for an ID. This has happened to me before and I never give it to them. I just say "I have my partner card..." and stare at them lol.
If you or anyone needs their physical card hop onto
$1 and there's a tab where you can get them to mail you the physical partner card for free :)