Hi @titantwo,
To be compliant with the Australian Standards and the National Construction Code, floor wastes installed in waterproofed areas should have a puddle flange, which is tied into the waterproofing membrane. What you have with the waterproofing membrane extending down into the waste pipe is much better than nothing, but it is not entirely compliant with modern standards. I think it is important to note that there is a more robust system designed for this application.
It is likely going to be worth speaking with a plumber about having a puddle flange installed, as this is the correct method of waterproofing this type of connection.
A screeding product like this Easy Mix Traditional Floor Screed, is often used to fill voids around puddle flanges, so this might be a suitable solution. I'd check with a plumber, though, just to be sure it is the best solution.
Let me know if you have further questions.
Jacob
