I have ‘Snap to Grid’ enabled, but the stamps are not snapping to the grid. What is going on?

Thanks for all the help. After learning that Acrobat DC either can't do what I need or there are subpar workarounds and script installs required, I found another program called PDF-XChange with a perpetual license (for a very modest fee) that can easily do literally everything I needed Acrobat DC to do, without requiring thousands of dollars in subscription fees over the course of a lifetime.