PLLC and testing

[retbenser]

Given:

30 doctors are members of a PLLC.

Doctors own about equal share (no one owns more than 80%) of the corporation.

Each doctor is a separate profit center (own client's income and expenses).

PLLC has a centralized billing department (where all doctors share expenses in the billing department).

Question:

Is it possible to establish a DB/DC combo plan for a single doctor but taking into account only his employees in the nondiscrimination testing and disregarding employees of the other doctors?

Thanks for all responses.