The failure rate on the Excelsior CPNE is approximately 35-36%.
The CPNE in Excelsior is so structured so as to minimize instructor bias and inadvertent errors on the part of the student.
As I remember it, two of the three clinicals must be passed in order to pass the CPNE.
As I remember it, every clinical is monitored by a different instructor.
This helps to minimize instructor bias.
Of course, despite all of the above, circumstances out of the instructors and/or students control may result in clinical failure.
My suggestion to you is to relax during the clinical and do your best knowing that the clinical may be taken over again.
Best of luck!