Unfortunately, since it is after the fact, there is not much you can do. Always ask about testing requirements on assignments before you sign any contract.
The fact that your recruiter didn't tell you about the PBDS is shady, and tells me they are dishonest. Don't let them tell you they didn't know about it- they know which hospitals require PBDS & which don't. I would find a recruiter you can trust & see if they can find you a different assignment.