@MplsCustomer Thank you very much for your feedback. In fact, my Google
home and two mini's were set up as different homes. It solved my problem
when I deleted those Mini's and added them as speakers under the same
home. Thank you!!
No, two other mini's are not hearing the visitor announcement. As an
example one of the mini's is on the second floor and the google home
announcement from the first floor is not audible.