Hi Linda,
Cineraria is toxic to many species when ingested, including dogs, cats and humans as well - all for the same reason. The plant contains pyrollizidine alkaloids, which cause liver damage in sufficient quantities. There are many plants containing these alkaloids. All need to be ingested to manifest this toxicity, which is dose dependent.
The most famous plant with these alkaloids is Comfrey, which was used orally for centuries, but is now only considered safe when used topically. If Comfrey is safe when used topically, I'm guessing Cineraria is, too, which might explain why you haven't been seeing any reactions.
Maybe take this information back to your team for them to explore and confirm, but from my perspective, topical use should be safe
Steve