I’m curious what an in person orientation does that a background check does not. In my experience, asking suspicious candidates to show me what is outside their window is enough to weed out North Korean candidates who are lying about their location. That is a much lower effort than an in-person orientation.
If you tell them during the call that after being hired they are required to be in office for an orientation, and ask them if that’s a possibility they will come up with an excuse. I did the same and saved me the awkward window question, which might as well be the sky or they might be in a room with no windows