I like the way it has gone from "Ocean levels are not rising in the Southern Hemisphere" to "It doesn't really matter if they are"!
The fact is sea levels can be measured, and sea level data has been recorded since at least the turn of the 20th Century.
Furthermore, sea level records for Australia and New Zealand show an overall rising of sea levels throughout that period, with the rate accelerating since 1993.
Coastal sea-level rise | Stats NZ
https://ecos.csiro.au/sea-level-rise-how-do-we-best-prepare/
Also, these statistics only confirm what even Blind Freddy can easily enough see for himself - with the cutting in half of Bribie Island being just one example of many.