Charging PCBU 2 for induction into PCBU 1 site HSWA gives the definition of a worker in Section 19:
19 Meaning of worker
(1) In this Act, unless the context otherwise requires,
a worker means an individual who carries out work in any capacity for a PCBU, including work as—
(a) an employee; or
(b) a contractor or subcontractor; or
(c) an employee of a contractor or subcontractor; or
(d) an employee of a labour hire company who has been assigned to work in the business or undertaking; or
(e) an outworker (including a homeworker); or
(f) an apprentice or a trainee; or
(g) a person gaining work experience or undertaking a work trial; or
(h) a volunteer worker; or
(i) a person of a prescribed class.
As the levy is not being put onto the individual there is no breach here.