Q1: If the wall to be papered was previously painted with latex paint, and the paint is mostly intact except for a few patches of blistering where I applied a few strips of wallpaper w/out primer(dumb!) and then removed it, should I use the Roman 909 wallpaper primer for ”sound paint” after I’ve patched the blistered areas?

Q2: For a ceiling application in a different room, where the textured ceiling was skim-coated and then painted with ceiling paint, is the Roman 999-RX35 for porous surfaces the best choice of primer before wallpaper?