Roommate brought back bouquet with lillies! What should I do to reduce risks

My roommate and I both have a cat, and she knew that lillies are toxic to cats because she brought back flowers before and I asked her, but somehow today she still brought them home! I only discovered after a while and immediately told her to throw them outside. She only threw away to lillies but still kept the rest of the bouquet (that very likely have lilly pollens on them).

My cat has ran towards her and rubbed her and rolled on the rug under the bouquet, so I washed my cat with water throughly and lock her in my own room. Then I told her to keep the bouquet in her own room, although I could see that she was really unhappy about it.

Now I'm very scared. What should I do to reduce the risk for my cat next? It is safe enough if I vacuum the floor and clean all the counters the lillies might have been touched? Since my roommate won't throw away the rest of the flowers, and she doesn't seem to shower everyday, I'm worried that she might bring out a little bit pollens on her moving. Would that little amount of pollens make cats ill (my cat loves rolling on the floor and rub on everything)?

Also, am I over-reacting? She also has a cat and she seemed to be fine just leaving the lilles on a shelf, so I don't know if she has done it before without any problem to her cat.