∀ {G : Type u_1} {P : Type u_2} [inst : PartialOrder G] [inst_1 : PartialOrder P] [inst_2 : VAdd G P]
  [inst_3 : IsOrderedCancelVAdd G P] {s : Set G} {t v : Set P} {hv : v.IsPWO} {a : P} {hs : s.IsPWO} {ht : t.IsPWO},
  v ⊆ t → Finset.VAddAntidiagonal hs hv a ⊆ Finset.VAddAntidiagonal hs ht a