It is unfortunate but there are these issues in all walks of life. I think that the laws against fraud and the Strata legislation are there and in most cases would be sufficient.
Also I read PeterC’s reply in the thread ‘conflict of interest’ about a ‘Code of Conduct’ and am not sure if it is in the governing statutes of other states but it is a good idea.
I know in practice it is not as easy as it sounds but in reality, the best and really only form of “intregity audit” is a vigilant and robust OC. Too often ECs are able to get away with things because other owners don’t want to take responsibility or perform duties.