main problem is thart PVA mainly stays on the surface as a film and very little penetrates the surface of the plaster. This means the mechanical key is relatively weak compared to a penetrative acrylic or epoxy primer. the only realistic way to get it off is to scarify it some how. wire brush, sander etc. There are one or two enclosed sanding systems available that limit the dust. The other issues are that if it gets wet (water based adhesive???) it re emulsifies. That will cause the tiles to fall off. Additionally if you can get them to stick Poly Vynil Acetate is highly susceptible to alkali burn which breaks it down over a period of time.
Has no place in tiling I am afraid.........
Well put mate. 🙂