Section 324 of the Fair Work Act 2009 provides:
Method and frequency of payment
(1) An employer must pay an employee … in money by one, or a combination, of the methods referred to in subsection (2) …
(2) The methods are as follows:
(a) cash;
(b) cheque, money order, postal order or similar order, payable to the employee;
(c) the use of an electronic funds transfer system to credit an account held by the employee;
(d) a method authorised under a modern award or an enterprise agreement.
(3) Despite paragraph (1)(b), if a modern award or an enterprise agreement specifies a particular method by which the money must be paid, then the employer must pay the money by that method.
I am not aware of anything in the employment law that would prohibit an award or agreement from nominating the financial institution. It may fall foul of third-line forcing but not if, for example, the employer was a financial institution that required the use of its own accounts (no 3rd party so no third-line forcing).
Putting that aside, the employer has an obligation to pay; the choice of method lies with the employer. If it is too hard to pay electronically (e.g. employee hasn't given accounts details, the account is in the Caymen Islands etc.) then they must pay in cash or by cheque/money order.