I'm thinking...
If the ruling stems on the concept that the screenings are not a part of the job - then the employees shouldn't participate in the screenings since they are not part of the job.
Then when they are fired for not participating in the screenings, they should sue for wrongful termination, and then in turn get the screenings recognized as being part of the job.
Then they can return to this issue and get it sorted out.
-scheherazade