I didn't get this email (remote, non-core). My personal email is populated in Workday because I anticipated being let go at some point. So maybe this is going out to users with a missing personal email. To your point, this is how you will get instructions to sign for salary continuation leave and the invitation for Displacement Orientation.
One of the things Displacement Operations told me when I had to displace somebody was to check in Workday to make sure the personal email was correct/present. Without knowing all the particulars of your situation, the change in communication pattern and request for personal email, in my opinion, might indicate you are part of an active displacement cohort or upcoming location disposition.