According to the “Who’s responsible …” Memorandum issued by the state government, the lot owner is responsible for the fixtures, fittings and tapware in the bathroom, while the owners corp is responsible for the original tiles and waterproofing (with some exceptions).
However, what complicates this is that the OC is also responsible for replacing or repairing any lot property that is damaged during a repair to common property.
Looking at the work outlined above, the taps and shower screen are all going to be reinstated and the brickwork and tiles are to be repaired and/or replaced – which brings us to the question of the bath.
The hole in the bath is not OC responsibility, but if the bath can’t be removed and replaced without significantly damaging it, then it should be replaced at the OC’s expense.
By the way, if the bath was damaged accidentally (rather than through wear and tear) the lot owner could probably make a claim through strata insurance.
I would try to ascertain whether or not the bath could reasonably be replaced intact in its current state. If not, then the OC is up for the cost of its replacement. If it could be put back, regardless of its present state, then the lot owner should be asked to pay for a new bath if they don’t want the old one reinstalled.