JWWC said:if someone was selling ditch lily seeds, word would get around.
Ditch lily 'Europa' is a triploid and seeds are very difficult to produce with its pollen from crosses with diploid pod parents but possibly somewhat easier with crosses to tetraploid pod parents - seeds from crosses using it as a pod parent are probably extremely rare.
If someone was selling seeds with incorrect parentage on purpose they would presumably be using a very pod fertile and common inexpensive cultivar.