You have a right to see any correspondence between the strata committee, and the strata manager acting on their behalf, and anyone else. You may, however have to pay a nominal fee of around $30 and attend the strata manager’s office to do so.
The only exception to your right to see correspondence might be if it was between them and their lawyer in a dispute with you. In this case, they may say it’s “commercial in confidence” but that is utter BS. You are contributing to the bills via your levies so you are entitled to see them.
I presume you think there is something fishy about their relationship with the firm they have contracted to do the work. Their secrecy does nothing to diminish that.